feat(node): Add MCP server auto instrumentation#16043

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feat(node): Add MCP server auto instrumentation #16043

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e0e9a2b
feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…
Apr 14, 2025
b323422
feat(node): Add MCP server auto instrumentation
Apr 14, 2025
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1 change: 1 addition & 0 deletions packages/core/src/index.ts
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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down
129 changes: 129 additions & 0 deletions packages/core/src/mcp-server.ts
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import { DEBUG_BUILD } from './debug-build';
import {
SEMANTIC_ATTRIBUTE_SENTRY_OP,
SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
// The first arg is always a name, the last arg should always be a callback function (ie a handler).
// TODO: We could also make use of the resource uri argument somehow.
resource: (name: string, ...args: unknown[]) => void;
// The first arg is always a name, the last arg should always be a callback function (ie a handler).
tool: (name: string, ...args: unknown[]) => void;
// The first arg is always a name, the last arg should always be a callback function (ie a handler).
prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
* Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
*
* Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
*/
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
if (wrappedMcpServerInstances.has(mcpServerInstance)) {
return mcpServerInstance;
}

if (!isMcpServerInstance(mcpServerInstance)) {
DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
return mcpServerInstance;
}

mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
apply(target, thisArg, argArray) {
const resourceName: unknown = argArray[0];
const resourceHandler: unknown = argArray[argArray.length - 1];

if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
return target.apply(thisArg, argArray);
}

return startSpan(
{
name: `mcp-server/resource:${resourceName}`,
forceTransaction: true,
attributes: {
[SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
'mcp_server.resource': resourceName,
},
},
() => target.apply(thisArg, argArray),
);
},
});

mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
apply(target, thisArg, argArray) {
const toolName: unknown = argArray[0];
const toolHandler: unknown = argArray[argArray.length - 1];

if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
return target.apply(thisArg, argArray);
}

return startSpan(
{
name: `mcp-server/tool:${toolName}`,
forceTransaction: true,
attributes: {
[SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
'mcp_server.tool': toolName,
},
},
() => target.apply(thisArg, argArray),
);
},
});

mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
apply(target, thisArg, argArray) {
const promptName: unknown = argArray[0];
const promptHandler: unknown = argArray[argArray.length - 1];

if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
return target.apply(thisArg, argArray);
}

return startSpan(
{
name: `mcp-server/resource:${promptName}`,
forceTransaction: true,
attributes: {
[SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
'mcp_server.prompt': promptName,
},
},
() => target.apply(thisArg, argArray),
);
},
});

wrappedMcpServerInstances.add(mcpServerInstance);

return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
return (
typeof mcpServerInstance === 'object' &&
mcpServerInstance !== null &&
'resource' in mcpServerInstance &&
typeof mcpServerInstance.resource === 'function' &&
'tool' in mcpServerInstance &&
typeof mcpServerInstance.tool === 'function' &&
'prompt' in mcpServerInstance &&
typeof mcpServerInstance.prompt === 'function'
);
}
242 changes: 242 additions & 0 deletions packages/core/test/lib/mcp-server.test.ts
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import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
SEMANTIC_ATTRIBUTE_SENTRY_OP,
SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
beforeEach(() => {
vi.clearAllMocks();
// @ts-expect-error mocking span is annoying
vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
});

it('should wrap valid MCP server instance methods with Sentry spans', () => {
// Create a mock MCP server instance
const mockResource = vi.fn();
const mockTool = vi.fn();
const mockPrompt = vi.fn();

const mockMcpServer = {
resource: mockResource,
tool: mockTool,
prompt: mockPrompt,
};

// Wrap the MCP server
const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

// Verify it returns the same instance (modified)
expect(wrappedMcpServer).toBe(mockMcpServer);

// Original methods should be wrapped
expect(wrappedMcpServer.resource).not.toBe(mockResource);
expect(wrappedMcpServer.tool).not.toBe(mockTool);
expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
});

it('should return the input unchanged if it is not a valid MCP server instance', () => {
const invalidMcpServer = {
// Missing required methods
resource: () => {},
tool: () => {},
// No prompt method
};

const result = wrapMcpServerWithSentry(invalidMcpServer);
expect(result).toBe(invalidMcpServer);

// Methods should not be wrapped
expect(result.resource).toBe(invalidMcpServer.resource);
expect(result.tool).toBe(invalidMcpServer.tool);

// No calls to startSpan
expect(tracingModule.startSpan).not.toHaveBeenCalled();
});

it('should not wrap the same instance twice', () => {
const mockMcpServer = {
resource: vi.fn(),
tool: vi.fn(),
prompt: vi.fn(),
};

// First wrap
const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

// Store references to wrapped methods
const wrappedResource = wrappedOnce.resource;
const wrappedTool = wrappedOnce.tool;
const wrappedPrompt = wrappedOnce.prompt;

// Second wrap
const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

// Should be the same instance with the same wrapped methods
expect(wrappedTwice).toBe(wrappedOnce);
expect(wrappedTwice.resource).toBe(wrappedResource);
expect(wrappedTwice.tool).toBe(wrappedTool);
expect(wrappedTwice.prompt).toBe(wrappedPrompt);
});

describe('resource method wrapping', () => {
it('should create a span with proper attributes when resource is called', () => {
const mockResourceHandler = vi.fn();
const resourceName = 'test-resource';

const mockMcpServer = {
resource: vi.fn(),
tool: vi.fn(),
prompt: vi.fn(),
};

const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
expect(tracingModule.startSpan).toHaveBeenCalledWith(
{
name: `mcp-server/resource:${resourceName}`,
forceTransaction: true,
attributes: {
[SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
'mcp_server.resource': resourceName,
},
},
expect.any(Function),
);

// Verify the original method was called with all arguments
expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
});

it('should call the original resource method directly if name or handler is not valid', () => {
const mockMcpServer = {
resource: vi.fn(),
tool: vi.fn(),
prompt: vi.fn(),
};

const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

// Call without string name
wrappedMcpServer.resource({} as any, 'handler');

// Call without function handler
wrappedMcpServer.resource('name', 'not-a-function');

// Original method should be called directly without creating spans
expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
expect(tracingModule.startSpan).not.toHaveBeenCalled();
});
});

describe('tool method wrapping', () => {
it('should create a span with proper attributes when tool is called', () => {
const mockToolHandler = vi.fn();
const toolName = 'test-tool';

const mockMcpServer = {
resource: vi.fn(),
tool: vi.fn(),
prompt: vi.fn(),
};

const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
wrappedMcpServer.tool(toolName, {}, mockToolHandler);

expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
expect(tracingModule.startSpan).toHaveBeenCalledWith(
{
name: `mcp-server/tool:${toolName}`,
forceTransaction: true,
attributes: {
[SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
'mcp_server.tool': toolName,
},
},
expect.any(Function),
);

// Verify the original method was called with all arguments
expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
});

it('should call the original tool method directly if name or handler is not valid', () => {
const mockMcpServer = {
resource: vi.fn(),
tool: vi.fn(),
prompt: vi.fn(),
};

const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

// Call without string name
wrappedMcpServer.tool({} as any, 'handler');

// Original method should be called directly without creating spans
expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
expect(tracingModule.startSpan).not.toHaveBeenCalled();
});
});

describe('prompt method wrapping', () => {
it('should create a span with proper attributes when prompt is called', () => {
const mockPromptHandler = vi.fn();
const promptName = 'test-prompt';

const mockMcpServer = {
resource: vi.fn(),
tool: vi.fn(),
prompt: vi.fn(),
};

const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
expect(tracingModule.startSpan).toHaveBeenCalledWith(
{
name: `mcp-server/resource:${promptName}`,
forceTransaction: true,
attributes: {
[SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
[SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
'mcp_server.prompt': promptName,
},
},
expect.any(Function),
);

// Verify the original method was called with all arguments
expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
});

it('should call the original prompt method directly if name or handler is not valid', () => {
const mockMcpServer = {
resource: vi.fn(),
tool: vi.fn(),
prompt: vi.fn(),
};

const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

// Call without function handler
wrappedMcpServer.prompt('name', 'not-a-function');

// Original method should be called directly without creating spans
expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
expect(tracingModule.startSpan).not.toHaveBeenCalled();
});
});
});
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 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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feat(node): Add MCP server auto instrumentation#16043

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lforst
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feat(node): Add MCP server auto instrumentation
#16043
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e0e9a2b

feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…

Apr 14, 2025
b323422

feat(node): Add MCP server auto instrumentation

Apr 14, 2025

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1 change: 1 addition & 0 deletions
packages/core/src/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down

129 changes: 129 additions & 0 deletions
packages/core/src/mcp-server.ts

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import { DEBUG_BUILD } from './debug-build';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 // TODO: We could also make use of the resource uri argument somehow.
 resource: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 tool: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
 * Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
 *
 * Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
 */
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
 if (wrappedMcpServerInstances.has(mcpServerInstance)) {
 return mcpServerInstance;
 }

 if (!isMcpServerInstance(mcpServerInstance)) {
 DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
 return mcpServerInstance;
 }

 mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
 apply(target, thisArg, argArray) {
 const resourceName: unknown = argArray[0];
 const resourceHandler: unknown = argArray[argArray.length - 1];

 if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
 apply(target, thisArg, argArray) {
 const toolName: unknown = argArray[0];
 const toolHandler: unknown = argArray[argArray.length - 1];

 if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
 apply(target, thisArg, argArray) {
 const promptName: unknown = argArray[0];
 const promptHandler: unknown = argArray[argArray.length - 1];

 if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 wrappedMcpServerInstances.add(mcpServerInstance);

 return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
 return (
 typeof mcpServerInstance === 'object' &&
 mcpServerInstance !== null &&
 'resource' in mcpServerInstance &&
 typeof mcpServerInstance.resource === 'function' &&
 'tool' in mcpServerInstance &&
 typeof mcpServerInstance.tool === 'function' &&
 'prompt' in mcpServerInstance &&
 typeof mcpServerInstance.prompt === 'function'
 );
}

242 changes: 242 additions & 0 deletions
packages/core/test/lib/mcp-server.test.ts

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import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
 beforeEach(() => {
 vi.clearAllMocks();
 // @ts-expect-error mocking span is annoying
 vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
 });

 it('should wrap valid MCP server instance methods with Sentry spans', () => {
 // Create a mock MCP server instance
 const mockResource = vi.fn();
 const mockTool = vi.fn();
 const mockPrompt = vi.fn();

 const mockMcpServer = {
 resource: mockResource,
 tool: mockTool,
 prompt: mockPrompt,
 };

 // Wrap the MCP server
 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Verify it returns the same instance (modified)
 expect(wrappedMcpServer).toBe(mockMcpServer);

 // Original methods should be wrapped
 expect(wrappedMcpServer.resource).not.toBe(mockResource);
 expect(wrappedMcpServer.tool).not.toBe(mockTool);
 expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
 });

 it('should return the input unchanged if it is not a valid MCP server instance', () => {
 const invalidMcpServer = {
 // Missing required methods
 resource: () => {},
 tool: () => {},
 // No prompt method
 };

 const result = wrapMcpServerWithSentry(invalidMcpServer);
 expect(result).toBe(invalidMcpServer);

 // Methods should not be wrapped
 expect(result.resource).toBe(invalidMcpServer.resource);
 expect(result.tool).toBe(invalidMcpServer.tool);

 // No calls to startSpan
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });

 it('should not wrap the same instance twice', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 // First wrap
 const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

 // Store references to wrapped methods
 const wrappedResource = wrappedOnce.resource;
 const wrappedTool = wrappedOnce.tool;
 const wrappedPrompt = wrappedOnce.prompt;

 // Second wrap
 const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

 // Should be the same instance with the same wrapped methods
 expect(wrappedTwice).toBe(wrappedOnce);
 expect(wrappedTwice.resource).toBe(wrappedResource);
 expect(wrappedTwice.tool).toBe(wrappedTool);
 expect(wrappedTwice.prompt).toBe(wrappedPrompt);
 });

 describe('resource method wrapping', () => {
 it('should create a span with proper attributes when resource is called', () => {
 const mockResourceHandler = vi.fn();
 const resourceName = 'test-resource';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
 });

 it('should call the original resource method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.resource({} as any, 'handler');

 // Call without function handler
 wrappedMcpServer.resource('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('tool method wrapping', () => {
 it('should create a span with proper attributes when tool is called', () => {
 const mockToolHandler = vi.fn();
 const toolName = 'test-tool';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.tool(toolName, {}, mockToolHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
 });

 it('should call the original tool method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.tool({} as any, 'handler');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('prompt method wrapping', () => {
 it('should create a span with proper attributes when prompt is called', () => {
 const mockPromptHandler = vi.fn();
 const promptName = 'test-prompt';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
 });

 it('should call the original prompt method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without function handler
 wrappedMcpServer.prompt('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });
});
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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feat(node): Add MCP server auto instrumentation#16043

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feat(node): Add MCP server auto instrumentation
#16043
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e0e9a2b

feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…

Apr 14, 2025
b323422

feat(node): Add MCP server auto instrumentation

Apr 14, 2025

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1 change: 1 addition & 0 deletions
packages/core/src/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down

129 changes: 129 additions & 0 deletions
packages/core/src/mcp-server.ts

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,129 @@
import { DEBUG_BUILD } from './debug-build';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 // TODO: We could also make use of the resource uri argument somehow.
 resource: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 tool: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
 * Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
 *
 * Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
 */
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
 if (wrappedMcpServerInstances.has(mcpServerInstance)) {
 return mcpServerInstance;
 }

 if (!isMcpServerInstance(mcpServerInstance)) {
 DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
 return mcpServerInstance;
 }

 mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
 apply(target, thisArg, argArray) {
 const resourceName: unknown = argArray[0];
 const resourceHandler: unknown = argArray[argArray.length - 1];

 if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
 apply(target, thisArg, argArray) {
 const toolName: unknown = argArray[0];
 const toolHandler: unknown = argArray[argArray.length - 1];

 if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
 apply(target, thisArg, argArray) {
 const promptName: unknown = argArray[0];
 const promptHandler: unknown = argArray[argArray.length - 1];

 if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 wrappedMcpServerInstances.add(mcpServerInstance);

 return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
 return (
 typeof mcpServerInstance === 'object' &&
 mcpServerInstance !== null &&
 'resource' in mcpServerInstance &&
 typeof mcpServerInstance.resource === 'function' &&
 'tool' in mcpServerInstance &&
 typeof mcpServerInstance.tool === 'function' &&
 'prompt' in mcpServerInstance &&
 typeof mcpServerInstance.prompt === 'function'
 );
}

242 changes: 242 additions & 0 deletions
packages/core/test/lib/mcp-server.test.ts

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,242 @@
import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
 beforeEach(() => {
 vi.clearAllMocks();
 // @ts-expect-error mocking span is annoying
 vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
 });

 it('should wrap valid MCP server instance methods with Sentry spans', () => {
 // Create a mock MCP server instance
 const mockResource = vi.fn();
 const mockTool = vi.fn();
 const mockPrompt = vi.fn();

 const mockMcpServer = {
 resource: mockResource,
 tool: mockTool,
 prompt: mockPrompt,
 };

 // Wrap the MCP server
 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Verify it returns the same instance (modified)
 expect(wrappedMcpServer).toBe(mockMcpServer);

 // Original methods should be wrapped
 expect(wrappedMcpServer.resource).not.toBe(mockResource);
 expect(wrappedMcpServer.tool).not.toBe(mockTool);
 expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
 });

 it('should return the input unchanged if it is not a valid MCP server instance', () => {
 const invalidMcpServer = {
 // Missing required methods
 resource: () => {},
 tool: () => {},
 // No prompt method
 };

 const result = wrapMcpServerWithSentry(invalidMcpServer);
 expect(result).toBe(invalidMcpServer);

 // Methods should not be wrapped
 expect(result.resource).toBe(invalidMcpServer.resource);
 expect(result.tool).toBe(invalidMcpServer.tool);

 // No calls to startSpan
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });

 it('should not wrap the same instance twice', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 // First wrap
 const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

 // Store references to wrapped methods
 const wrappedResource = wrappedOnce.resource;
 const wrappedTool = wrappedOnce.tool;
 const wrappedPrompt = wrappedOnce.prompt;

 // Second wrap
 const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

 // Should be the same instance with the same wrapped methods
 expect(wrappedTwice).toBe(wrappedOnce);
 expect(wrappedTwice.resource).toBe(wrappedResource);
 expect(wrappedTwice.tool).toBe(wrappedTool);
 expect(wrappedTwice.prompt).toBe(wrappedPrompt);
 });

 describe('resource method wrapping', () => {
 it('should create a span with proper attributes when resource is called', () => {
 const mockResourceHandler = vi.fn();
 const resourceName = 'test-resource';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
 });

 it('should call the original resource method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.resource({} as any, 'handler');

 // Call without function handler
 wrappedMcpServer.resource('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('tool method wrapping', () => {
 it('should create a span with proper attributes when tool is called', () => {
 const mockToolHandler = vi.fn();
 const toolName = 'test-tool';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.tool(toolName, {}, mockToolHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
 });

 it('should call the original tool method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.tool({} as any, 'handler');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('prompt method wrapping', () => {
 it('should create a span with proper attributes when prompt is called', () => {
 const mockPromptHandler = vi.fn();
 const promptName = 'test-prompt';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
 });

 it('should call the original prompt method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without function handler
 wrappedMcpServer.prompt('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });
});
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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feat(node): Add MCP server auto instrumentation#16043

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 Closed

lforst
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feat(node): Add MCP server auto instrumentation
#16043
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e0e9a2b

feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…

Apr 14, 2025
b323422

feat(node): Add MCP server auto instrumentation

Apr 14, 2025

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1 change: 1 addition & 0 deletions
packages/core/src/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down

129 changes: 129 additions & 0 deletions
packages/core/src/mcp-server.ts

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,129 @@
import { DEBUG_BUILD } from './debug-build';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 // TODO: We could also make use of the resource uri argument somehow.
 resource: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 tool: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
 * Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
 *
 * Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
 */
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
 if (wrappedMcpServerInstances.has(mcpServerInstance)) {
 return mcpServerInstance;
 }

 if (!isMcpServerInstance(mcpServerInstance)) {
 DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
 return mcpServerInstance;
 }

 mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
 apply(target, thisArg, argArray) {
 const resourceName: unknown = argArray[0];
 const resourceHandler: unknown = argArray[argArray.length - 1];

 if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
 apply(target, thisArg, argArray) {
 const toolName: unknown = argArray[0];
 const toolHandler: unknown = argArray[argArray.length - 1];

 if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
 apply(target, thisArg, argArray) {
 const promptName: unknown = argArray[0];
 const promptHandler: unknown = argArray[argArray.length - 1];

 if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 wrappedMcpServerInstances.add(mcpServerInstance);

 return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
 return (
 typeof mcpServerInstance === 'object' &&
 mcpServerInstance !== null &&
 'resource' in mcpServerInstance &&
 typeof mcpServerInstance.resource === 'function' &&
 'tool' in mcpServerInstance &&
 typeof mcpServerInstance.tool === 'function' &&
 'prompt' in mcpServerInstance &&
 typeof mcpServerInstance.prompt === 'function'
 );
}

242 changes: 242 additions & 0 deletions
packages/core/test/lib/mcp-server.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,242 @@
import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
 beforeEach(() => {
 vi.clearAllMocks();
 // @ts-expect-error mocking span is annoying
 vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
 });

 it('should wrap valid MCP server instance methods with Sentry spans', () => {
 // Create a mock MCP server instance
 const mockResource = vi.fn();
 const mockTool = vi.fn();
 const mockPrompt = vi.fn();

 const mockMcpServer = {
 resource: mockResource,
 tool: mockTool,
 prompt: mockPrompt,
 };

 // Wrap the MCP server
 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Verify it returns the same instance (modified)
 expect(wrappedMcpServer).toBe(mockMcpServer);

 // Original methods should be wrapped
 expect(wrappedMcpServer.resource).not.toBe(mockResource);
 expect(wrappedMcpServer.tool).not.toBe(mockTool);
 expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
 });

 it('should return the input unchanged if it is not a valid MCP server instance', () => {
 const invalidMcpServer = {
 // Missing required methods
 resource: () => {},
 tool: () => {},
 // No prompt method
 };

 const result = wrapMcpServerWithSentry(invalidMcpServer);
 expect(result).toBe(invalidMcpServer);

 // Methods should not be wrapped
 expect(result.resource).toBe(invalidMcpServer.resource);
 expect(result.tool).toBe(invalidMcpServer.tool);

 // No calls to startSpan
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });

 it('should not wrap the same instance twice', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 // First wrap
 const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

 // Store references to wrapped methods
 const wrappedResource = wrappedOnce.resource;
 const wrappedTool = wrappedOnce.tool;
 const wrappedPrompt = wrappedOnce.prompt;

 // Second wrap
 const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

 // Should be the same instance with the same wrapped methods
 expect(wrappedTwice).toBe(wrappedOnce);
 expect(wrappedTwice.resource).toBe(wrappedResource);
 expect(wrappedTwice.tool).toBe(wrappedTool);
 expect(wrappedTwice.prompt).toBe(wrappedPrompt);
 });

 describe('resource method wrapping', () => {
 it('should create a span with proper attributes when resource is called', () => {
 const mockResourceHandler = vi.fn();
 const resourceName = 'test-resource';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
 });

 it('should call the original resource method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.resource({} as any, 'handler');

 // Call without function handler
 wrappedMcpServer.resource('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('tool method wrapping', () => {
 it('should create a span with proper attributes when tool is called', () => {
 const mockToolHandler = vi.fn();
 const toolName = 'test-tool';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.tool(toolName, {}, mockToolHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
 });

 it('should call the original tool method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.tool({} as any, 'handler');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('prompt method wrapping', () => {
 it('should create a span with proper attributes when prompt is called', () => {
 const mockPromptHandler = vi.fn();
 const promptName = 'test-prompt';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
 });

 it('should call the original prompt method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without function handler
 wrappedMcpServer.prompt('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });
});
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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feat(node): Add MCP server auto instrumentation
#16043
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e0e9a2b

feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…

Apr 14, 2025
b323422

feat(node): Add MCP server auto instrumentation

Apr 14, 2025

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1 change: 1 addition & 0 deletions
packages/core/src/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down

129 changes: 129 additions & 0 deletions
packages/core/src/mcp-server.ts

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,129 @@
import { DEBUG_BUILD } from './debug-build';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 // TODO: We could also make use of the resource uri argument somehow.
 resource: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 tool: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
 * Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
 *
 * Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
 */
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
 if (wrappedMcpServerInstances.has(mcpServerInstance)) {
 return mcpServerInstance;
 }

 if (!isMcpServerInstance(mcpServerInstance)) {
 DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
 return mcpServerInstance;
 }

 mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
 apply(target, thisArg, argArray) {
 const resourceName: unknown = argArray[0];
 const resourceHandler: unknown = argArray[argArray.length - 1];

 if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
 apply(target, thisArg, argArray) {
 const toolName: unknown = argArray[0];
 const toolHandler: unknown = argArray[argArray.length - 1];

 if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
 apply(target, thisArg, argArray) {
 const promptName: unknown = argArray[0];
 const promptHandler: unknown = argArray[argArray.length - 1];

 if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 wrappedMcpServerInstances.add(mcpServerInstance);

 return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
 return (
 typeof mcpServerInstance === 'object' &&
 mcpServerInstance !== null &&
 'resource' in mcpServerInstance &&
 typeof mcpServerInstance.resource === 'function' &&
 'tool' in mcpServerInstance &&
 typeof mcpServerInstance.tool === 'function' &&
 'prompt' in mcpServerInstance &&
 typeof mcpServerInstance.prompt === 'function'
 );
}

242 changes: 242 additions & 0 deletions
packages/core/test/lib/mcp-server.test.ts

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,242 @@
import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
 beforeEach(() => {
 vi.clearAllMocks();
 // @ts-expect-error mocking span is annoying
 vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
 });

 it('should wrap valid MCP server instance methods with Sentry spans', () => {
 // Create a mock MCP server instance
 const mockResource = vi.fn();
 const mockTool = vi.fn();
 const mockPrompt = vi.fn();

 const mockMcpServer = {
 resource: mockResource,
 tool: mockTool,
 prompt: mockPrompt,
 };

 // Wrap the MCP server
 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Verify it returns the same instance (modified)
 expect(wrappedMcpServer).toBe(mockMcpServer);

 // Original methods should be wrapped
 expect(wrappedMcpServer.resource).not.toBe(mockResource);
 expect(wrappedMcpServer.tool).not.toBe(mockTool);
 expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
 });

 it('should return the input unchanged if it is not a valid MCP server instance', () => {
 const invalidMcpServer = {
 // Missing required methods
 resource: () => {},
 tool: () => {},
 // No prompt method
 };

 const result = wrapMcpServerWithSentry(invalidMcpServer);
 expect(result).toBe(invalidMcpServer);

 // Methods should not be wrapped
 expect(result.resource).toBe(invalidMcpServer.resource);
 expect(result.tool).toBe(invalidMcpServer.tool);

 // No calls to startSpan
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });

 it('should not wrap the same instance twice', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 // First wrap
 const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

 // Store references to wrapped methods
 const wrappedResource = wrappedOnce.resource;
 const wrappedTool = wrappedOnce.tool;
 const wrappedPrompt = wrappedOnce.prompt;

 // Second wrap
 const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

 // Should be the same instance with the same wrapped methods
 expect(wrappedTwice).toBe(wrappedOnce);
 expect(wrappedTwice.resource).toBe(wrappedResource);
 expect(wrappedTwice.tool).toBe(wrappedTool);
 expect(wrappedTwice.prompt).toBe(wrappedPrompt);
 });

 describe('resource method wrapping', () => {
 it('should create a span with proper attributes when resource is called', () => {
 const mockResourceHandler = vi.fn();
 const resourceName = 'test-resource';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
 });

 it('should call the original resource method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.resource({} as any, 'handler');

 // Call without function handler
 wrappedMcpServer.resource('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('tool method wrapping', () => {
 it('should create a span with proper attributes when tool is called', () => {
 const mockToolHandler = vi.fn();
 const toolName = 'test-tool';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.tool(toolName, {}, mockToolHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
 });

 it('should call the original tool method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.tool({} as any, 'handler');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('prompt method wrapping', () => {
 it('should create a span with proper attributes when prompt is called', () => {
 const mockPromptHandler = vi.fn();
 const promptName = 'test-prompt';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
 });

 it('should call the original prompt method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without function handler
 wrappedMcpServer.prompt('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });
});
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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feat(node): Add MCP server auto instrumentation#16043

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 Closed

lforst
wants to merge
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commits into

from

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feat(node): Add MCP server auto instrumentation
#16043
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e0e9a2b

feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…

Apr 14, 2025
b323422

feat(node): Add MCP server auto instrumentation

Apr 14, 2025

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1 change: 1 addition & 0 deletions
packages/core/src/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down

129 changes: 129 additions & 0 deletions
packages/core/src/mcp-server.ts

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import { DEBUG_BUILD } from './debug-build';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 // TODO: We could also make use of the resource uri argument somehow.
 resource: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 tool: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
 * Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
 *
 * Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
 */
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
 if (wrappedMcpServerInstances.has(mcpServerInstance)) {
 return mcpServerInstance;
 }

 if (!isMcpServerInstance(mcpServerInstance)) {
 DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
 return mcpServerInstance;
 }

 mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
 apply(target, thisArg, argArray) {
 const resourceName: unknown = argArray[0];
 const resourceHandler: unknown = argArray[argArray.length - 1];

 if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
 apply(target, thisArg, argArray) {
 const toolName: unknown = argArray[0];
 const toolHandler: unknown = argArray[argArray.length - 1];

 if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
 apply(target, thisArg, argArray) {
 const promptName: unknown = argArray[0];
 const promptHandler: unknown = argArray[argArray.length - 1];

 if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 wrappedMcpServerInstances.add(mcpServerInstance);

 return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
 return (
 typeof mcpServerInstance === 'object' &&
 mcpServerInstance !== null &&
 'resource' in mcpServerInstance &&
 typeof mcpServerInstance.resource === 'function' &&
 'tool' in mcpServerInstance &&
 typeof mcpServerInstance.tool === 'function' &&
 'prompt' in mcpServerInstance &&
 typeof mcpServerInstance.prompt === 'function'
 );
}

242 changes: 242 additions & 0 deletions
packages/core/test/lib/mcp-server.test.ts

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import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
 beforeEach(() => {
 vi.clearAllMocks();
 // @ts-expect-error mocking span is annoying
 vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
 });

 it('should wrap valid MCP server instance methods with Sentry spans', () => {
 // Create a mock MCP server instance
 const mockResource = vi.fn();
 const mockTool = vi.fn();
 const mockPrompt = vi.fn();

 const mockMcpServer = {
 resource: mockResource,
 tool: mockTool,
 prompt: mockPrompt,
 };

 // Wrap the MCP server
 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Verify it returns the same instance (modified)
 expect(wrappedMcpServer).toBe(mockMcpServer);

 // Original methods should be wrapped
 expect(wrappedMcpServer.resource).not.toBe(mockResource);
 expect(wrappedMcpServer.tool).not.toBe(mockTool);
 expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
 });

 it('should return the input unchanged if it is not a valid MCP server instance', () => {
 const invalidMcpServer = {
 // Missing required methods
 resource: () => {},
 tool: () => {},
 // No prompt method
 };

 const result = wrapMcpServerWithSentry(invalidMcpServer);
 expect(result).toBe(invalidMcpServer);

 // Methods should not be wrapped
 expect(result.resource).toBe(invalidMcpServer.resource);
 expect(result.tool).toBe(invalidMcpServer.tool);

 // No calls to startSpan
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });

 it('should not wrap the same instance twice', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 // First wrap
 const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

 // Store references to wrapped methods
 const wrappedResource = wrappedOnce.resource;
 const wrappedTool = wrappedOnce.tool;
 const wrappedPrompt = wrappedOnce.prompt;

 // Second wrap
 const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

 // Should be the same instance with the same wrapped methods
 expect(wrappedTwice).toBe(wrappedOnce);
 expect(wrappedTwice.resource).toBe(wrappedResource);
 expect(wrappedTwice.tool).toBe(wrappedTool);
 expect(wrappedTwice.prompt).toBe(wrappedPrompt);
 });

 describe('resource method wrapping', () => {
 it('should create a span with proper attributes when resource is called', () => {
 const mockResourceHandler = vi.fn();
 const resourceName = 'test-resource';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
 });

 it('should call the original resource method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.resource({} as any, 'handler');

 // Call without function handler
 wrappedMcpServer.resource('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('tool method wrapping', () => {
 it('should create a span with proper attributes when tool is called', () => {
 const mockToolHandler = vi.fn();
 const toolName = 'test-tool';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.tool(toolName, {}, mockToolHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
 });

 it('should call the original tool method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.tool({} as any, 'handler');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('prompt method wrapping', () => {
 it('should create a span with proper attributes when prompt is called', () => {
 const mockPromptHandler = vi.fn();
 const promptName = 'test-prompt';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
 });

 it('should call the original prompt method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without function handler
 wrappedMcpServer.prompt('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });
});
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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feat(node): Add MCP server auto instrumentation
#16043
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e0e9a2b

feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…

Apr 14, 2025
b323422

feat(node): Add MCP server auto instrumentation

Apr 14, 2025

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1 change: 1 addition & 0 deletions
packages/core/src/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down

129 changes: 129 additions & 0 deletions
packages/core/src/mcp-server.ts

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Original file line numberDiff line numberDiff line change
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import { DEBUG_BUILD } from './debug-build';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 // TODO: We could also make use of the resource uri argument somehow.
 resource: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 tool: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
 * Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
 *
 * Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
 */
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
 if (wrappedMcpServerInstances.has(mcpServerInstance)) {
 return mcpServerInstance;
 }

 if (!isMcpServerInstance(mcpServerInstance)) {
 DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
 return mcpServerInstance;
 }

 mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
 apply(target, thisArg, argArray) {
 const resourceName: unknown = argArray[0];
 const resourceHandler: unknown = argArray[argArray.length - 1];

 if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
 apply(target, thisArg, argArray) {
 const toolName: unknown = argArray[0];
 const toolHandler: unknown = argArray[argArray.length - 1];

 if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
 apply(target, thisArg, argArray) {
 const promptName: unknown = argArray[0];
 const promptHandler: unknown = argArray[argArray.length - 1];

 if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 wrappedMcpServerInstances.add(mcpServerInstance);

 return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
 return (
 typeof mcpServerInstance === 'object' &&
 mcpServerInstance !== null &&
 'resource' in mcpServerInstance &&
 typeof mcpServerInstance.resource === 'function' &&
 'tool' in mcpServerInstance &&
 typeof mcpServerInstance.tool === 'function' &&
 'prompt' in mcpServerInstance &&
 typeof mcpServerInstance.prompt === 'function'
 );
}

242 changes: 242 additions & 0 deletions
packages/core/test/lib/mcp-server.test.ts

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import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
 beforeEach(() => {
 vi.clearAllMocks();
 // @ts-expect-error mocking span is annoying
 vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
 });

 it('should wrap valid MCP server instance methods with Sentry spans', () => {
 // Create a mock MCP server instance
 const mockResource = vi.fn();
 const mockTool = vi.fn();
 const mockPrompt = vi.fn();

 const mockMcpServer = {
 resource: mockResource,
 tool: mockTool,
 prompt: mockPrompt,
 };

 // Wrap the MCP server
 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Verify it returns the same instance (modified)
 expect(wrappedMcpServer).toBe(mockMcpServer);

 // Original methods should be wrapped
 expect(wrappedMcpServer.resource).not.toBe(mockResource);
 expect(wrappedMcpServer.tool).not.toBe(mockTool);
 expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
 });

 it('should return the input unchanged if it is not a valid MCP server instance', () => {
 const invalidMcpServer = {
 // Missing required methods
 resource: () => {},
 tool: () => {},
 // No prompt method
 };

 const result = wrapMcpServerWithSentry(invalidMcpServer);
 expect(result).toBe(invalidMcpServer);

 // Methods should not be wrapped
 expect(result.resource).toBe(invalidMcpServer.resource);
 expect(result.tool).toBe(invalidMcpServer.tool);

 // No calls to startSpan
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });

 it('should not wrap the same instance twice', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 // First wrap
 const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

 // Store references to wrapped methods
 const wrappedResource = wrappedOnce.resource;
 const wrappedTool = wrappedOnce.tool;
 const wrappedPrompt = wrappedOnce.prompt;

 // Second wrap
 const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

 // Should be the same instance with the same wrapped methods
 expect(wrappedTwice).toBe(wrappedOnce);
 expect(wrappedTwice.resource).toBe(wrappedResource);
 expect(wrappedTwice.tool).toBe(wrappedTool);
 expect(wrappedTwice.prompt).toBe(wrappedPrompt);
 });

 describe('resource method wrapping', () => {
 it('should create a span with proper attributes when resource is called', () => {
 const mockResourceHandler = vi.fn();
 const resourceName = 'test-resource';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
 });

 it('should call the original resource method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.resource({} as any, 'handler');

 // Call without function handler
 wrappedMcpServer.resource('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('tool method wrapping', () => {
 it('should create a span with proper attributes when tool is called', () => {
 const mockToolHandler = vi.fn();
 const toolName = 'test-tool';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.tool(toolName, {}, mockToolHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
 });

 it('should call the original tool method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.tool({} as any, 'handler');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('prompt method wrapping', () => {
 it('should create a span with proper attributes when prompt is called', () => {
 const mockPromptHandler = vi.fn();
 const promptName = 'test-prompt';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
 });

 it('should call the original prompt method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without function handler
 wrappedMcpServer.prompt('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });
});
Loading

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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feat(node): Add MCP server auto instrumentation
#16043
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e0e9a2b

feat(core): Add `wrapMcpServerWithSentry` to instrument MCP servers f…

Apr 14, 2025
b323422

feat(node): Add MCP server auto instrumentation

Apr 14, 2025

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1 change: 1 addition & 0 deletions
packages/core/src/index.ts

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Original file line numberDiff line numberDiff line change
Expand Up@@ -111,6 +111,7 @@ export { thirdPartyErrorFilterIntegration } from './integrations/third-party-err
export { profiler } from './profiling';
export { instrumentFetchRequest } from './fetch';
export { trpcMiddleware } from './trpc';
export { wrapMcpServerWithSentry } from './mcp-server';
export { captureFeedback } from './feedback';
export type { ReportDialogOptions } from './report-dialog';
export { _INTERNAL_captureLog, _INTERNAL_flushLogsBuffer } from './logs/exports';
Expand Down

129 changes: 129 additions & 0 deletions
packages/core/src/mcp-server.ts

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,129 @@
import { DEBUG_BUILD } from './debug-build';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from './semanticAttributes';
import { startSpan } from './tracing';
import { logger } from './utils-hoist';

interface MCPServerInstance {
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 // TODO: We could also make use of the resource uri argument somehow.
 resource: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 tool: (name: string, ...args: unknown[]) => void;
 // The first arg is always a name, the last arg should always be a callback function (ie a handler).
 prompt: (name: string, ...args: unknown[]) => void;
}

const wrappedMcpServerInstances = new WeakSet();

/**
 * Wraps a MCP Server instance from the `@modelcontextprotocol/sdk` package with Sentry instrumentation.
 *
 * Compatible with versions `^1.9.0` of the `@modelcontextprotocol/sdk` package.
 */
// We are exposing this API for non-node runtimes that cannot rely on auto-instrumentation.
export function wrapMcpServerWithSentry<S extends object>(mcpServerInstance: S): S {
 if (wrappedMcpServerInstances.has(mcpServerInstance)) {
 return mcpServerInstance;
 }

 if (!isMcpServerInstance(mcpServerInstance)) {
 DEBUG_BUILD && logger.warn('Did not patch MCP server. Interface is incompatible.');
 return mcpServerInstance;
 }

 mcpServerInstance.resource = new Proxy(mcpServerInstance.resource, {
 apply(target, thisArg, argArray) {
 const resourceName: unknown = argArray[0];
 const resourceHandler: unknown = argArray[argArray.length - 1];

 if (typeof resourceName !== 'string' || typeof resourceHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.tool = new Proxy(mcpServerInstance.tool, {
 apply(target, thisArg, argArray) {
 const toolName: unknown = argArray[0];
 const toolHandler: unknown = argArray[argArray.length - 1];

 if (typeof toolName !== 'string' || typeof toolHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 mcpServerInstance.prompt = new Proxy(mcpServerInstance.prompt, {
 apply(target, thisArg, argArray) {
 const promptName: unknown = argArray[0];
 const promptHandler: unknown = argArray[argArray.length - 1];

 if (typeof promptName !== 'string' || typeof promptHandler !== 'function') {
 return target.apply(thisArg, argArray);
 }

 return startSpan(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 () => target.apply(thisArg, argArray),
 );
 },
 });

 wrappedMcpServerInstances.add(mcpServerInstance);

 return mcpServerInstance as S;
}

function isMcpServerInstance(mcpServerInstance: unknown): mcpServerInstance is MCPServerInstance {
 return (
 typeof mcpServerInstance === 'object' &&
 mcpServerInstance !== null &&
 'resource' in mcpServerInstance &&
 typeof mcpServerInstance.resource === 'function' &&
 'tool' in mcpServerInstance &&
 typeof mcpServerInstance.tool === 'function' &&
 'prompt' in mcpServerInstance &&
 typeof mcpServerInstance.prompt === 'function'
 );
}

242 changes: 242 additions & 0 deletions
packages/core/test/lib/mcp-server.test.ts

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import { beforeEach, describe, expect, it, vi } from 'vitest';
import { wrapMcpServerWithSentry } from '../../src/mcp-server';
import {
 SEMANTIC_ATTRIBUTE_SENTRY_OP,
 SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN,
 SEMANTIC_ATTRIBUTE_SENTRY_SOURCE,
} from '../../src/semanticAttributes';
import * as tracingModule from '../../src/tracing';

vi.mock('../../src/tracing');

describe('wrapMcpServerWithSentry', () => {
 beforeEach(() => {
 vi.clearAllMocks();
 // @ts-expect-error mocking span is annoying
 vi.mocked(tracingModule.startSpan).mockImplementation((_, cb) => cb());
 });

 it('should wrap valid MCP server instance methods with Sentry spans', () => {
 // Create a mock MCP server instance
 const mockResource = vi.fn();
 const mockTool = vi.fn();
 const mockPrompt = vi.fn();

 const mockMcpServer = {
 resource: mockResource,
 tool: mockTool,
 prompt: mockPrompt,
 };

 // Wrap the MCP server
 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Verify it returns the same instance (modified)
 expect(wrappedMcpServer).toBe(mockMcpServer);

 // Original methods should be wrapped
 expect(wrappedMcpServer.resource).not.toBe(mockResource);
 expect(wrappedMcpServer.tool).not.toBe(mockTool);
 expect(wrappedMcpServer.prompt).not.toBe(mockPrompt);
 });

 it('should return the input unchanged if it is not a valid MCP server instance', () => {
 const invalidMcpServer = {
 // Missing required methods
 resource: () => {},
 tool: () => {},
 // No prompt method
 };

 const result = wrapMcpServerWithSentry(invalidMcpServer);
 expect(result).toBe(invalidMcpServer);

 // Methods should not be wrapped
 expect(result.resource).toBe(invalidMcpServer.resource);
 expect(result.tool).toBe(invalidMcpServer.tool);

 // No calls to startSpan
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });

 it('should not wrap the same instance twice', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 // First wrap
 const wrappedOnce = wrapMcpServerWithSentry(mockMcpServer);

 // Store references to wrapped methods
 const wrappedResource = wrappedOnce.resource;
 const wrappedTool = wrappedOnce.tool;
 const wrappedPrompt = wrappedOnce.prompt;

 // Second wrap
 const wrappedTwice = wrapMcpServerWithSentry(wrappedOnce);

 // Should be the same instance with the same wrapped methods
 expect(wrappedTwice).toBe(wrappedOnce);
 expect(wrappedTwice.resource).toBe(wrappedResource);
 expect(wrappedTwice.tool).toBe(wrappedTool);
 expect(wrappedTwice.prompt).toBe(wrappedPrompt);
 });

 describe('resource method wrapping', () => {
 it('should create a span with proper attributes when resource is called', () => {
 const mockResourceHandler = vi.fn();
 const resourceName = 'test-resource';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.resource(resourceName, {}, mockResourceHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${resourceName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.resource': resourceName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.resource).toHaveBeenCalledWith(resourceName, {}, mockResourceHandler);
 });

 it('should call the original resource method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.resource({} as any, 'handler');

 // Call without function handler
 wrappedMcpServer.resource('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.resource).toHaveBeenCalledTimes(2);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('tool method wrapping', () => {
 it('should create a span with proper attributes when tool is called', () => {
 const mockToolHandler = vi.fn();
 const toolName = 'test-tool';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.tool(toolName, {}, mockToolHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/tool:${toolName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.tool': toolName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.tool).toHaveBeenCalledWith(toolName, {}, mockToolHandler);
 });

 it('should call the original tool method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without string name
 wrappedMcpServer.tool({} as any, 'handler');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.tool).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });

 describe('prompt method wrapping', () => {
 it('should create a span with proper attributes when prompt is called', () => {
 const mockPromptHandler = vi.fn();
 const promptName = 'test-prompt';

 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);
 wrappedMcpServer.prompt(promptName, {}, mockPromptHandler);

 expect(tracingModule.startSpan).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).toHaveBeenCalledWith(
 {
 name: `mcp-server/resource:${promptName}`,
 forceTransaction: true,
 attributes: {
 [SEMANTIC_ATTRIBUTE_SENTRY_OP]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_ORIGIN]: 'auto.function.mcp-server',
 [SEMANTIC_ATTRIBUTE_SENTRY_SOURCE]: 'route',
 'mcp_server.prompt': promptName,
 },
 },
 expect.any(Function),
 );

 // Verify the original method was called with all arguments
 expect(mockMcpServer.prompt).toHaveBeenCalledWith(promptName, {}, mockPromptHandler);
 });

 it('should call the original prompt method directly if name or handler is not valid', () => {
 const mockMcpServer = {
 resource: vi.fn(),
 tool: vi.fn(),
 prompt: vi.fn(),
 };

 const wrappedMcpServer = wrapMcpServerWithSentry(mockMcpServer);

 // Call without function handler
 wrappedMcpServer.prompt('name', 'not-a-function');

 // Original method should be called directly without creating spans
 expect(mockMcpServer.prompt).toHaveBeenCalledTimes(1);
 expect(tracingModule.startSpan).not.toHaveBeenCalled();
 });
 });
});
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