fix(server): bound mcp tool payloads on the wire#5481

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fix(server): bound mcp tool payloads on the wire #5481

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88 changes: 86 additions & 2 deletions apps/server/src/orchestration/ActivityPayloadProjection.ts
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
* Fields of an MCP tool call item worth shipping: everything that describes
* the call itself. `result` is handled separately because it carries the
* unbounded tool output.
*/
const MCP_ITEM_DESCRIPTOR_FIELDS = [
"type",
"id",
"tool",
"server",
"status",
"arguments",
"appContext",
"error",
"durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
* MCP results carry their payload in `result.content`, either as a plain
* string or as the MCP content-block array (`[{ type: "text", text }, …]`).
* Flattens the leading text so the shared tool-output summarizer can bound it.
*/
function extractMcpResultText(content: unknown): string | null {
if (typeof content === "string") {
return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
}
if (!Array.isArray(content)) {
return null;
}
let joined = "";
for (const block of content) {
const text = asTrimmedString(asRecord(block)?.text);
if (!text) {
continue;
}
joined = joined.length > 0 ? `${joined}\n${text}` : text;
if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
break;
}
}
return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
* Bounds an MCP tool call item for the wire. Both clients render `data.item`
* as JSON in the expanded work-log row, so the call descriptor stays intact
* while `result` — which carries the whole tool result, routinely a megabyte
* for connector fetches — collapses to the same one-line preview regular tool
* output gets. An item record always projects to a record so the clients'
* `data.item !== undefined` check keeps holding.
*/
function projectMcpToolCallData(
data: Record<string, unknown>,
): Record<string, unknown> | undefined {
const item = asRecord(data.item);
if (!item) {
return undefined;
}

const projectedItem: Record<string, unknown> = {};
for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
if (field in item) {
projectedItem[field] = item[field];
}
}

const result = asRecord(item.result);
if (result) {
const text = extractMcpResultText(result.content);
const summary = text ? summarizeToolTextOutput(text) : null;
projectedItem.result = {
...(summary ? { content: summary } : {}),
// MCP signals tool-level failure on the result, not on `item.error`.
...(result.isError === true ? { isError: true } : {}),
};
}

return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
const lines: string[] = [];
for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
const payload = asRecord(activity.payload);
const data = asRecord(payload?.data);
if (!payload || !data || payload.itemType === "mcp_tool_call") {
if (!payload || !data) {
return activity;
}

const projectedData: Record<string, unknown> = {};
const item = projectCommandData(data);
const item =
payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
if (item) {
projectedData.item = item;
}
Expand Down
120 changes: 113 additions & 7 deletions apps/server/test/ActivityPayloadProjection.test.ts
View file
Open in desktop
Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
}),
makeActivity("mcp", "mcp_tool_call", {
item: {
type: "mcpToolCall",
id: "mcp_1",
server: "repository",
tool: "search",
arguments: { query: "activity projection" },
aggregatedOutput: "mcp payload remains available",
status: "completed",
durationMs: 12,
error: null,
result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
aggregatedOutput: "bulk that no client reads",
},
ignored: "MCP data is rendered verbatim",
toolCallId: "tool-mcp",
ignored: "top-level bulk",
}),
makeActivity("search", "web_search", {
rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
});
});

it("passes MCP tool data through unchanged", () => {
expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
it("keeps the MCP call descriptor and bounds its result", () => {
const projected = projectActivityPayload(fixtures[4]!);

expect(projected.payload).toEqual({
itemType: "mcp_tool_call",
title: "mcp_tool_call",
detail: "mcp_tool_call detail",
status: "completed",
requestKind: "command",
data: {
item: {
type: "mcpToolCall",
id: "mcp_1",
tool: "search",
server: "repository",
status: "completed",
arguments: { query: "activity projection" },
error: null,
durationMs: 12,
result: { content: "first result line" },
},
toolCallId: "tool-mcp",
},
});
});

it("bounds a megabyte-scale MCP result", () => {
const huge = makeActivity("mcp-huge", "mcp_tool_call", {
item: {
server: "github",
tool: "fetch_pr",
arguments: { number: 5219 },
status: "completed",
result: {
content: [
{ type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
{ type: "text", text: "x".repeat(200_000) },
],
},
},
});

const projected = projectActivityPayload(huge);
const projectedSize = JSON.stringify(projected.payload).length;

expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
expect(projectedSize).toBeLessThan(500);
expect(projected.payload).toMatchObject({
data: {
item: {
server: "github",
tool: "fetch_pr",
arguments: { number: 5219 },
status: "completed",
result: { content: "pull request body" },
},
},
});
});

it("keeps a failing MCP call's error and isError flag", () => {
const failed = makeActivity("mcp-error", "mcp_tool_call", {
item: {
server: "github",
tool: "fetch_pr",
status: "failed",
error: { message: "not found", code: 404 },
result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
},
});

expect(projectActivityPayload(failed).payload).toMatchObject({
data: {
item: {
error: { message: "not found", code: 404 },
result: { content: "HTTP 404", isError: true },
},
},
});
});

it("keeps in-flight MCP calls renderable without a result", () => {
const started: OrchestrationThreadActivity = {
...makeActivity("mcp-started", "mcp_tool_call", {
item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
}),
kind: "tool.started",
};

const projected = projectActivityPayload(started);
const data = (projected.payload as { data: Record<string, unknown> }).data;

// The clients gate the expanded body on `data.item !== undefined`.
expect(data.item).toEqual({
server: "github",
tool: "fetch_pr",
arguments: {},
status: "inProgress",
});
});

it("keeps current web and mobile derived output identical for every tool item type", () => {
for (const activity of fixtures) {
it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
for (const activity of fixtures.filter(
(fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
)) {
const projected = projectActivityPayload(activity);
expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
snapshotSequence: 7,
thread: makeThread([fixtures[4]!]),
});
expect(projected.thread.activities).toEqual([fixtures[4]]);
expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
});

it("does not filter live activity-appended events", () => {
Expand Down
Loading
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 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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fix(server): bound mcp tool payloads on the wire#5481

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commit into

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fix(server): bound mcp tool payloads on the wire
#5481
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88 changes: 86 additions & 2 deletions
apps/server/src/orchestration/ActivityPayloadProjection.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
 return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
 * Fields of an MCP tool call item worth shipping: everything that describes
 * the call itself. `result` is handled separately because it carries the
 * unbounded tool output.
 */
const MCP_ITEM_DESCRIPTOR_FIELDS = [
 "type",
 "id",
 "tool",
 "server",
 "status",
 "arguments",
 "appContext",
 "error",
 "durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
 * MCP results carry their payload in `result.content`, either as a plain
 * string or as the MCP content-block array (`[{ type: "text", text }, …]`).
 * Flattens the leading text so the shared tool-output summarizer can bound it.
 */
function extractMcpResultText(content: unknown): string | null {
 if (typeof content === "string") {
 return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
 }
 if (!Array.isArray(content)) {
 return null;
 }
 let joined = "";
 for (const block of content) {
 const text = asTrimmedString(asRecord(block)?.text);
 if (!text) {
 continue;
 }
 joined = joined.length > 0 ? `${joined}\n${text}` : text;
 if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
 break;
 }
 }
 return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
 * Bounds an MCP tool call item for the wire. Both clients render `data.item`
 * as JSON in the expanded work-log row, so the call descriptor stays intact
 * while `result` — which carries the whole tool result, routinely a megabyte
 * for connector fetches — collapses to the same one-line preview regular tool
 * output gets. An item record always projects to a record so the clients'
 * `data.item !== undefined` check keeps holding.
 */
function projectMcpToolCallData(
 data: Record<string, unknown>,
): Record<string, unknown> | undefined {
 const item = asRecord(data.item);
 if (!item) {
 return undefined;
 }

 const projectedItem: Record<string, unknown> = {};
 for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
 if (field in item) {
 projectedItem[field] = item[field];
 }
 }

 const result = asRecord(item.result);
 if (result) {
 const text = extractMcpResultText(result.content);
 const summary = text ? summarizeToolTextOutput(text) : null;
 projectedItem.result = {
 ...(summary ? { content: summary } : {}),
 // MCP signals tool-level failure on the result, not on `item.error`.
 ...(result.isError === true ? { isError: true } : {}),
 };
 }

 return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
 const lines: string[] = [];
 for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
 const payload = asRecord(activity.payload);
 const data = asRecord(payload?.data);
 if (!payload || !data || payload.itemType === "mcp_tool_call") {
 if (!payload || !data) {
 return activity;
 }

 const projectedData: Record<string, unknown> = {};
 const item = projectCommandData(data);
 const item =
 payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
 if (item) {
 projectedData.item = item;
 }
Expand Down

120 changes: 113 additions & 7 deletions
apps/server/test/ActivityPayloadProjection.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
 }),
 makeActivity("mcp", "mcp_tool_call", {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 server: "repository",
 tool: "search",
 arguments: { query: "activity projection" },
 aggregatedOutput: "mcp payload remains available",
 status: "completed",
 durationMs: 12,
 error: null,
 result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
 aggregatedOutput: "bulk that no client reads",
 },
 ignored: "MCP data is rendered verbatim",
 toolCallId: "tool-mcp",
 ignored: "top-level bulk",
 }),
 makeActivity("search", "web_search", {
 rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
 });
 });

 it("passes MCP tool data through unchanged", () => {
 expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
 it("keeps the MCP call descriptor and bounds its result", () => {
 const projected = projectActivityPayload(fixtures[4]!);

 expect(projected.payload).toEqual({
 itemType: "mcp_tool_call",
 title: "mcp_tool_call",
 detail: "mcp_tool_call detail",
 status: "completed",
 requestKind: "command",
 data: {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 tool: "search",
 server: "repository",
 status: "completed",
 arguments: { query: "activity projection" },
 error: null,
 durationMs: 12,
 result: { content: "first result line" },
 },
 toolCallId: "tool-mcp",
 },
 });
 });

 it("bounds a megabyte-scale MCP result", () => {
 const huge = makeActivity("mcp-huge", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: {
 content: [
 { type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
 { type: "text", text: "x".repeat(200_000) },
 ],
 },
 },
 });

 const projected = projectActivityPayload(huge);
 const projectedSize = JSON.stringify(projected.payload).length;

 expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
 expect(projectedSize).toBeLessThan(500);
 expect(projected.payload).toMatchObject({
 data: {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: { content: "pull request body" },
 },
 },
 });
 });

 it("keeps a failing MCP call's error and isError flag", () => {
 const failed = makeActivity("mcp-error", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 status: "failed",
 error: { message: "not found", code: 404 },
 result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
 },
 });

 expect(projectActivityPayload(failed).payload).toMatchObject({
 data: {
 item: {
 error: { message: "not found", code: 404 },
 result: { content: "HTTP 404", isError: true },
 },
 },
 });
 });

 it("keeps in-flight MCP calls renderable without a result", () => {
 const started: OrchestrationThreadActivity = {
 ...makeActivity("mcp-started", "mcp_tool_call", {
 item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
 }),
 kind: "tool.started",
 };

 const projected = projectActivityPayload(started);
 const data = (projected.payload as { data: Record<string, unknown> }).data;

 // The clients gate the expanded body on `data.item !== undefined`.
 expect(data.item).toEqual({
 server: "github",
 tool: "fetch_pr",
 arguments: {},
 status: "inProgress",
 });
 });

 it("keeps current web and mobile derived output identical for every tool item type", () => {
 for (const activity of fixtures) {
 it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
 for (const activity of fixtures.filter(
 (fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
 )) {
 const projected = projectActivityPayload(activity);
 expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
 expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
 snapshotSequence: 7,
 thread: makeThread([fixtures[4]!]),
 });
 expect(projected.thread.activities).toEqual([fixtures[4]]);
 expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
 });

 it("does not filter live activity-appended events", () => {
Expand Down
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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fix(server): bound mcp tool payloads on the wire#5481

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 Closed

t3dotgg
wants to merge
1
commit into

from

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fix(server): bound mcp tool payloads on the wire
#5481
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88 changes: 86 additions & 2 deletions
apps/server/src/orchestration/ActivityPayloadProjection.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
 return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
 * Fields of an MCP tool call item worth shipping: everything that describes
 * the call itself. `result` is handled separately because it carries the
 * unbounded tool output.
 */
const MCP_ITEM_DESCRIPTOR_FIELDS = [
 "type",
 "id",
 "tool",
 "server",
 "status",
 "arguments",
 "appContext",
 "error",
 "durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
 * MCP results carry their payload in `result.content`, either as a plain
 * string or as the MCP content-block array (`[{ type: "text", text }, …]`).
 * Flattens the leading text so the shared tool-output summarizer can bound it.
 */
function extractMcpResultText(content: unknown): string | null {
 if (typeof content === "string") {
 return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
 }
 if (!Array.isArray(content)) {
 return null;
 }
 let joined = "";
 for (const block of content) {
 const text = asTrimmedString(asRecord(block)?.text);
 if (!text) {
 continue;
 }
 joined = joined.length > 0 ? `${joined}\n${text}` : text;
 if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
 break;
 }
 }
 return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
 * Bounds an MCP tool call item for the wire. Both clients render `data.item`
 * as JSON in the expanded work-log row, so the call descriptor stays intact
 * while `result` — which carries the whole tool result, routinely a megabyte
 * for connector fetches — collapses to the same one-line preview regular tool
 * output gets. An item record always projects to a record so the clients'
 * `data.item !== undefined` check keeps holding.
 */
function projectMcpToolCallData(
 data: Record<string, unknown>,
): Record<string, unknown> | undefined {
 const item = asRecord(data.item);
 if (!item) {
 return undefined;
 }

 const projectedItem: Record<string, unknown> = {};
 for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
 if (field in item) {
 projectedItem[field] = item[field];
 }
 }

 const result = asRecord(item.result);
 if (result) {
 const text = extractMcpResultText(result.content);
 const summary = text ? summarizeToolTextOutput(text) : null;
 projectedItem.result = {
 ...(summary ? { content: summary } : {}),
 // MCP signals tool-level failure on the result, not on `item.error`.
 ...(result.isError === true ? { isError: true } : {}),
 };
 }

 return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
 const lines: string[] = [];
 for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
 const payload = asRecord(activity.payload);
 const data = asRecord(payload?.data);
 if (!payload || !data || payload.itemType === "mcp_tool_call") {
 if (!payload || !data) {
 return activity;
 }

 const projectedData: Record<string, unknown> = {};
 const item = projectCommandData(data);
 const item =
 payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
 if (item) {
 projectedData.item = item;
 }
Expand Down

120 changes: 113 additions & 7 deletions
apps/server/test/ActivityPayloadProjection.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
 }),
 makeActivity("mcp", "mcp_tool_call", {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 server: "repository",
 tool: "search",
 arguments: { query: "activity projection" },
 aggregatedOutput: "mcp payload remains available",
 status: "completed",
 durationMs: 12,
 error: null,
 result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
 aggregatedOutput: "bulk that no client reads",
 },
 ignored: "MCP data is rendered verbatim",
 toolCallId: "tool-mcp",
 ignored: "top-level bulk",
 }),
 makeActivity("search", "web_search", {
 rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
 });
 });

 it("passes MCP tool data through unchanged", () => {
 expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
 it("keeps the MCP call descriptor and bounds its result", () => {
 const projected = projectActivityPayload(fixtures[4]!);

 expect(projected.payload).toEqual({
 itemType: "mcp_tool_call",
 title: "mcp_tool_call",
 detail: "mcp_tool_call detail",
 status: "completed",
 requestKind: "command",
 data: {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 tool: "search",
 server: "repository",
 status: "completed",
 arguments: { query: "activity projection" },
 error: null,
 durationMs: 12,
 result: { content: "first result line" },
 },
 toolCallId: "tool-mcp",
 },
 });
 });

 it("bounds a megabyte-scale MCP result", () => {
 const huge = makeActivity("mcp-huge", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: {
 content: [
 { type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
 { type: "text", text: "x".repeat(200_000) },
 ],
 },
 },
 });

 const projected = projectActivityPayload(huge);
 const projectedSize = JSON.stringify(projected.payload).length;

 expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
 expect(projectedSize).toBeLessThan(500);
 expect(projected.payload).toMatchObject({
 data: {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: { content: "pull request body" },
 },
 },
 });
 });

 it("keeps a failing MCP call's error and isError flag", () => {
 const failed = makeActivity("mcp-error", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 status: "failed",
 error: { message: "not found", code: 404 },
 result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
 },
 });

 expect(projectActivityPayload(failed).payload).toMatchObject({
 data: {
 item: {
 error: { message: "not found", code: 404 },
 result: { content: "HTTP 404", isError: true },
 },
 },
 });
 });

 it("keeps in-flight MCP calls renderable without a result", () => {
 const started: OrchestrationThreadActivity = {
 ...makeActivity("mcp-started", "mcp_tool_call", {
 item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
 }),
 kind: "tool.started",
 };

 const projected = projectActivityPayload(started);
 const data = (projected.payload as { data: Record<string, unknown> }).data;

 // The clients gate the expanded body on `data.item !== undefined`.
 expect(data.item).toEqual({
 server: "github",
 tool: "fetch_pr",
 arguments: {},
 status: "inProgress",
 });
 });

 it("keeps current web and mobile derived output identical for every tool item type", () => {
 for (const activity of fixtures) {
 it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
 for (const activity of fixtures.filter(
 (fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
 )) {
 const projected = projectActivityPayload(activity);
 expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
 expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
 snapshotSequence: 7,
 thread: makeThread([fixtures[4]!]),
 });
 expect(projected.thread.activities).toEqual([fixtures[4]]);
 expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
 });

 it("does not filter live activity-appended events", () => {
Expand Down
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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fix(server): bound mcp tool payloads on the wire#5481

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fix(server): bound mcp tool payloads on the wire
#5481
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88 changes: 86 additions & 2 deletions
apps/server/src/orchestration/ActivityPayloadProjection.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
 return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
 * Fields of an MCP tool call item worth shipping: everything that describes
 * the call itself. `result` is handled separately because it carries the
 * unbounded tool output.
 */
const MCP_ITEM_DESCRIPTOR_FIELDS = [
 "type",
 "id",
 "tool",
 "server",
 "status",
 "arguments",
 "appContext",
 "error",
 "durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
 * MCP results carry their payload in `result.content`, either as a plain
 * string or as the MCP content-block array (`[{ type: "text", text }, …]`).
 * Flattens the leading text so the shared tool-output summarizer can bound it.
 */
function extractMcpResultText(content: unknown): string | null {
 if (typeof content === "string") {
 return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
 }
 if (!Array.isArray(content)) {
 return null;
 }
 let joined = "";
 for (const block of content) {
 const text = asTrimmedString(asRecord(block)?.text);
 if (!text) {
 continue;
 }
 joined = joined.length > 0 ? `${joined}\n${text}` : text;
 if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
 break;
 }
 }
 return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
 * Bounds an MCP tool call item for the wire. Both clients render `data.item`
 * as JSON in the expanded work-log row, so the call descriptor stays intact
 * while `result` — which carries the whole tool result, routinely a megabyte
 * for connector fetches — collapses to the same one-line preview regular tool
 * output gets. An item record always projects to a record so the clients'
 * `data.item !== undefined` check keeps holding.
 */
function projectMcpToolCallData(
 data: Record<string, unknown>,
): Record<string, unknown> | undefined {
 const item = asRecord(data.item);
 if (!item) {
 return undefined;
 }

 const projectedItem: Record<string, unknown> = {};
 for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
 if (field in item) {
 projectedItem[field] = item[field];
 }
 }

 const result = asRecord(item.result);
 if (result) {
 const text = extractMcpResultText(result.content);
 const summary = text ? summarizeToolTextOutput(text) : null;
 projectedItem.result = {
 ...(summary ? { content: summary } : {}),
 // MCP signals tool-level failure on the result, not on `item.error`.
 ...(result.isError === true ? { isError: true } : {}),
 };
 }

 return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
 const lines: string[] = [];
 for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
 const payload = asRecord(activity.payload);
 const data = asRecord(payload?.data);
 if (!payload || !data || payload.itemType === "mcp_tool_call") {
 if (!payload || !data) {
 return activity;
 }

 const projectedData: Record<string, unknown> = {};
 const item = projectCommandData(data);
 const item =
 payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
 if (item) {
 projectedData.item = item;
 }
Expand Down

120 changes: 113 additions & 7 deletions
apps/server/test/ActivityPayloadProjection.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
 }),
 makeActivity("mcp", "mcp_tool_call", {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 server: "repository",
 tool: "search",
 arguments: { query: "activity projection" },
 aggregatedOutput: "mcp payload remains available",
 status: "completed",
 durationMs: 12,
 error: null,
 result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
 aggregatedOutput: "bulk that no client reads",
 },
 ignored: "MCP data is rendered verbatim",
 toolCallId: "tool-mcp",
 ignored: "top-level bulk",
 }),
 makeActivity("search", "web_search", {
 rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
 });
 });

 it("passes MCP tool data through unchanged", () => {
 expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
 it("keeps the MCP call descriptor and bounds its result", () => {
 const projected = projectActivityPayload(fixtures[4]!);

 expect(projected.payload).toEqual({
 itemType: "mcp_tool_call",
 title: "mcp_tool_call",
 detail: "mcp_tool_call detail",
 status: "completed",
 requestKind: "command",
 data: {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 tool: "search",
 server: "repository",
 status: "completed",
 arguments: { query: "activity projection" },
 error: null,
 durationMs: 12,
 result: { content: "first result line" },
 },
 toolCallId: "tool-mcp",
 },
 });
 });

 it("bounds a megabyte-scale MCP result", () => {
 const huge = makeActivity("mcp-huge", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: {
 content: [
 { type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
 { type: "text", text: "x".repeat(200_000) },
 ],
 },
 },
 });

 const projected = projectActivityPayload(huge);
 const projectedSize = JSON.stringify(projected.payload).length;

 expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
 expect(projectedSize).toBeLessThan(500);
 expect(projected.payload).toMatchObject({
 data: {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: { content: "pull request body" },
 },
 },
 });
 });

 it("keeps a failing MCP call's error and isError flag", () => {
 const failed = makeActivity("mcp-error", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 status: "failed",
 error: { message: "not found", code: 404 },
 result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
 },
 });

 expect(projectActivityPayload(failed).payload).toMatchObject({
 data: {
 item: {
 error: { message: "not found", code: 404 },
 result: { content: "HTTP 404", isError: true },
 },
 },
 });
 });

 it("keeps in-flight MCP calls renderable without a result", () => {
 const started: OrchestrationThreadActivity = {
 ...makeActivity("mcp-started", "mcp_tool_call", {
 item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
 }),
 kind: "tool.started",
 };

 const projected = projectActivityPayload(started);
 const data = (projected.payload as { data: Record<string, unknown> }).data;

 // The clients gate the expanded body on `data.item !== undefined`.
 expect(data.item).toEqual({
 server: "github",
 tool: "fetch_pr",
 arguments: {},
 status: "inProgress",
 });
 });

 it("keeps current web and mobile derived output identical for every tool item type", () => {
 for (const activity of fixtures) {
 it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
 for (const activity of fixtures.filter(
 (fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
 )) {
 const projected = projectActivityPayload(activity);
 expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
 expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
 snapshotSequence: 7,
 thread: makeThread([fixtures[4]!]),
 });
 expect(projected.thread.activities).toEqual([fixtures[4]]);
 expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
 });

 it("does not filter live activity-appended events", () => {
Expand Down
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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fix(server): bound mcp tool payloads on the wire#5481

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 Closed

t3dotgg
wants to merge
1
commit into

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fix(server): bound mcp tool payloads on the wire
#5481
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88 changes: 86 additions & 2 deletions
apps/server/src/orchestration/ActivityPayloadProjection.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
 return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
 * Fields of an MCP tool call item worth shipping: everything that describes
 * the call itself. `result` is handled separately because it carries the
 * unbounded tool output.
 */
const MCP_ITEM_DESCRIPTOR_FIELDS = [
 "type",
 "id",
 "tool",
 "server",
 "status",
 "arguments",
 "appContext",
 "error",
 "durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
 * MCP results carry their payload in `result.content`, either as a plain
 * string or as the MCP content-block array (`[{ type: "text", text }, …]`).
 * Flattens the leading text so the shared tool-output summarizer can bound it.
 */
function extractMcpResultText(content: unknown): string | null {
 if (typeof content === "string") {
 return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
 }
 if (!Array.isArray(content)) {
 return null;
 }
 let joined = "";
 for (const block of content) {
 const text = asTrimmedString(asRecord(block)?.text);
 if (!text) {
 continue;
 }
 joined = joined.length > 0 ? `${joined}\n${text}` : text;
 if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
 break;
 }
 }
 return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
 * Bounds an MCP tool call item for the wire. Both clients render `data.item`
 * as JSON in the expanded work-log row, so the call descriptor stays intact
 * while `result` — which carries the whole tool result, routinely a megabyte
 * for connector fetches — collapses to the same one-line preview regular tool
 * output gets. An item record always projects to a record so the clients'
 * `data.item !== undefined` check keeps holding.
 */
function projectMcpToolCallData(
 data: Record<string, unknown>,
): Record<string, unknown> | undefined {
 const item = asRecord(data.item);
 if (!item) {
 return undefined;
 }

 const projectedItem: Record<string, unknown> = {};
 for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
 if (field in item) {
 projectedItem[field] = item[field];
 }
 }

 const result = asRecord(item.result);
 if (result) {
 const text = extractMcpResultText(result.content);
 const summary = text ? summarizeToolTextOutput(text) : null;
 projectedItem.result = {
 ...(summary ? { content: summary } : {}),
 // MCP signals tool-level failure on the result, not on `item.error`.
 ...(result.isError === true ? { isError: true } : {}),
 };
 }

 return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
 const lines: string[] = [];
 for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
 const payload = asRecord(activity.payload);
 const data = asRecord(payload?.data);
 if (!payload || !data || payload.itemType === "mcp_tool_call") {
 if (!payload || !data) {
 return activity;
 }

 const projectedData: Record<string, unknown> = {};
 const item = projectCommandData(data);
 const item =
 payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
 if (item) {
 projectedData.item = item;
 }
Expand Down

120 changes: 113 additions & 7 deletions
apps/server/test/ActivityPayloadProjection.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
 }),
 makeActivity("mcp", "mcp_tool_call", {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 server: "repository",
 tool: "search",
 arguments: { query: "activity projection" },
 aggregatedOutput: "mcp payload remains available",
 status: "completed",
 durationMs: 12,
 error: null,
 result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
 aggregatedOutput: "bulk that no client reads",
 },
 ignored: "MCP data is rendered verbatim",
 toolCallId: "tool-mcp",
 ignored: "top-level bulk",
 }),
 makeActivity("search", "web_search", {
 rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
 });
 });

 it("passes MCP tool data through unchanged", () => {
 expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
 it("keeps the MCP call descriptor and bounds its result", () => {
 const projected = projectActivityPayload(fixtures[4]!);

 expect(projected.payload).toEqual({
 itemType: "mcp_tool_call",
 title: "mcp_tool_call",
 detail: "mcp_tool_call detail",
 status: "completed",
 requestKind: "command",
 data: {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 tool: "search",
 server: "repository",
 status: "completed",
 arguments: { query: "activity projection" },
 error: null,
 durationMs: 12,
 result: { content: "first result line" },
 },
 toolCallId: "tool-mcp",
 },
 });
 });

 it("bounds a megabyte-scale MCP result", () => {
 const huge = makeActivity("mcp-huge", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: {
 content: [
 { type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
 { type: "text", text: "x".repeat(200_000) },
 ],
 },
 },
 });

 const projected = projectActivityPayload(huge);
 const projectedSize = JSON.stringify(projected.payload).length;

 expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
 expect(projectedSize).toBeLessThan(500);
 expect(projected.payload).toMatchObject({
 data: {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: { content: "pull request body" },
 },
 },
 });
 });

 it("keeps a failing MCP call's error and isError flag", () => {
 const failed = makeActivity("mcp-error", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 status: "failed",
 error: { message: "not found", code: 404 },
 result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
 },
 });

 expect(projectActivityPayload(failed).payload).toMatchObject({
 data: {
 item: {
 error: { message: "not found", code: 404 },
 result: { content: "HTTP 404", isError: true },
 },
 },
 });
 });

 it("keeps in-flight MCP calls renderable without a result", () => {
 const started: OrchestrationThreadActivity = {
 ...makeActivity("mcp-started", "mcp_tool_call", {
 item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
 }),
 kind: "tool.started",
 };

 const projected = projectActivityPayload(started);
 const data = (projected.payload as { data: Record<string, unknown> }).data;

 // The clients gate the expanded body on `data.item !== undefined`.
 expect(data.item).toEqual({
 server: "github",
 tool: "fetch_pr",
 arguments: {},
 status: "inProgress",
 });
 });

 it("keeps current web and mobile derived output identical for every tool item type", () => {
 for (const activity of fixtures) {
 it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
 for (const activity of fixtures.filter(
 (fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
 )) {
 const projected = projectActivityPayload(activity);
 expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
 expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
 snapshotSequence: 7,
 thread: makeThread([fixtures[4]!]),
 });
 expect(projected.thread.activities).toEqual([fixtures[4]]);
 expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
 });

 it("does not filter live activity-appended events", () => {
Expand Down
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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fix(server): bound mcp tool payloads on the wire#5481

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fix(server): bound mcp tool payloads on the wire
#5481
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88 changes: 86 additions & 2 deletions
apps/server/src/orchestration/ActivityPayloadProjection.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
 return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
 * Fields of an MCP tool call item worth shipping: everything that describes
 * the call itself. `result` is handled separately because it carries the
 * unbounded tool output.
 */
const MCP_ITEM_DESCRIPTOR_FIELDS = [
 "type",
 "id",
 "tool",
 "server",
 "status",
 "arguments",
 "appContext",
 "error",
 "durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
 * MCP results carry their payload in `result.content`, either as a plain
 * string or as the MCP content-block array (`[{ type: "text", text }, …]`).
 * Flattens the leading text so the shared tool-output summarizer can bound it.
 */
function extractMcpResultText(content: unknown): string | null {
 if (typeof content === "string") {
 return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
 }
 if (!Array.isArray(content)) {
 return null;
 }
 let joined = "";
 for (const block of content) {
 const text = asTrimmedString(asRecord(block)?.text);
 if (!text) {
 continue;
 }
 joined = joined.length > 0 ? `${joined}\n${text}` : text;
 if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
 break;
 }
 }
 return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
 * Bounds an MCP tool call item for the wire. Both clients render `data.item`
 * as JSON in the expanded work-log row, so the call descriptor stays intact
 * while `result` — which carries the whole tool result, routinely a megabyte
 * for connector fetches — collapses to the same one-line preview regular tool
 * output gets. An item record always projects to a record so the clients'
 * `data.item !== undefined` check keeps holding.
 */
function projectMcpToolCallData(
 data: Record<string, unknown>,
): Record<string, unknown> | undefined {
 const item = asRecord(data.item);
 if (!item) {
 return undefined;
 }

 const projectedItem: Record<string, unknown> = {};
 for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
 if (field in item) {
 projectedItem[field] = item[field];
 }
 }

 const result = asRecord(item.result);
 if (result) {
 const text = extractMcpResultText(result.content);
 const summary = text ? summarizeToolTextOutput(text) : null;
 projectedItem.result = {
 ...(summary ? { content: summary } : {}),
 // MCP signals tool-level failure on the result, not on `item.error`.
 ...(result.isError === true ? { isError: true } : {}),
 };
 }

 return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
 const lines: string[] = [];
 for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
 const payload = asRecord(activity.payload);
 const data = asRecord(payload?.data);
 if (!payload || !data || payload.itemType === "mcp_tool_call") {
 if (!payload || !data) {
 return activity;
 }

 const projectedData: Record<string, unknown> = {};
 const item = projectCommandData(data);
 const item =
 payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
 if (item) {
 projectedData.item = item;
 }
Expand Down

120 changes: 113 additions & 7 deletions
apps/server/test/ActivityPayloadProjection.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
 }),
 makeActivity("mcp", "mcp_tool_call", {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 server: "repository",
 tool: "search",
 arguments: { query: "activity projection" },
 aggregatedOutput: "mcp payload remains available",
 status: "completed",
 durationMs: 12,
 error: null,
 result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
 aggregatedOutput: "bulk that no client reads",
 },
 ignored: "MCP data is rendered verbatim",
 toolCallId: "tool-mcp",
 ignored: "top-level bulk",
 }),
 makeActivity("search", "web_search", {
 rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
 });
 });

 it("passes MCP tool data through unchanged", () => {
 expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
 it("keeps the MCP call descriptor and bounds its result", () => {
 const projected = projectActivityPayload(fixtures[4]!);

 expect(projected.payload).toEqual({
 itemType: "mcp_tool_call",
 title: "mcp_tool_call",
 detail: "mcp_tool_call detail",
 status: "completed",
 requestKind: "command",
 data: {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 tool: "search",
 server: "repository",
 status: "completed",
 arguments: { query: "activity projection" },
 error: null,
 durationMs: 12,
 result: { content: "first result line" },
 },
 toolCallId: "tool-mcp",
 },
 });
 });

 it("bounds a megabyte-scale MCP result", () => {
 const huge = makeActivity("mcp-huge", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: {
 content: [
 { type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
 { type: "text", text: "x".repeat(200_000) },
 ],
 },
 },
 });

 const projected = projectActivityPayload(huge);
 const projectedSize = JSON.stringify(projected.payload).length;

 expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
 expect(projectedSize).toBeLessThan(500);
 expect(projected.payload).toMatchObject({
 data: {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: { content: "pull request body" },
 },
 },
 });
 });

 it("keeps a failing MCP call's error and isError flag", () => {
 const failed = makeActivity("mcp-error", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 status: "failed",
 error: { message: "not found", code: 404 },
 result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
 },
 });

 expect(projectActivityPayload(failed).payload).toMatchObject({
 data: {
 item: {
 error: { message: "not found", code: 404 },
 result: { content: "HTTP 404", isError: true },
 },
 },
 });
 });

 it("keeps in-flight MCP calls renderable without a result", () => {
 const started: OrchestrationThreadActivity = {
 ...makeActivity("mcp-started", "mcp_tool_call", {
 item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
 }),
 kind: "tool.started",
 };

 const projected = projectActivityPayload(started);
 const data = (projected.payload as { data: Record<string, unknown> }).data;

 // The clients gate the expanded body on `data.item !== undefined`.
 expect(data.item).toEqual({
 server: "github",
 tool: "fetch_pr",
 arguments: {},
 status: "inProgress",
 });
 });

 it("keeps current web and mobile derived output identical for every tool item type", () => {
 for (const activity of fixtures) {
 it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
 for (const activity of fixtures.filter(
 (fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
 )) {
 const projected = projectActivityPayload(activity);
 expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
 expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
 snapshotSequence: 7,
 thread: makeThread([fixtures[4]!]),
 });
 expect(projected.thread.activities).toEqual([fixtures[4]]);
 expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
 });

 it("does not filter live activity-appended events", () => {
Expand Down
Loading

, '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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fix(server): bound mcp tool payloads on the wire#5481

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 Closed

t3dotgg
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commit into

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fix(server): bound mcp tool payloads on the wire
#5481
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88 changes: 86 additions & 2 deletions
apps/server/src/orchestration/ActivityPayloadProjection.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
 return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
 * Fields of an MCP tool call item worth shipping: everything that describes
 * the call itself. `result` is handled separately because it carries the
 * unbounded tool output.
 */
const MCP_ITEM_DESCRIPTOR_FIELDS = [
 "type",
 "id",
 "tool",
 "server",
 "status",
 "arguments",
 "appContext",
 "error",
 "durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
 * MCP results carry their payload in `result.content`, either as a plain
 * string or as the MCP content-block array (`[{ type: "text", text }, …]`).
 * Flattens the leading text so the shared tool-output summarizer can bound it.
 */
function extractMcpResultText(content: unknown): string | null {
 if (typeof content === "string") {
 return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
 }
 if (!Array.isArray(content)) {
 return null;
 }
 let joined = "";
 for (const block of content) {
 const text = asTrimmedString(asRecord(block)?.text);
 if (!text) {
 continue;
 }
 joined = joined.length > 0 ? `${joined}\n${text}` : text;
 if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
 break;
 }
 }
 return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
 * Bounds an MCP tool call item for the wire. Both clients render `data.item`
 * as JSON in the expanded work-log row, so the call descriptor stays intact
 * while `result` — which carries the whole tool result, routinely a megabyte
 * for connector fetches — collapses to the same one-line preview regular tool
 * output gets. An item record always projects to a record so the clients'
 * `data.item !== undefined` check keeps holding.
 */
function projectMcpToolCallData(
 data: Record<string, unknown>,
): Record<string, unknown> | undefined {
 const item = asRecord(data.item);
 if (!item) {
 return undefined;
 }

 const projectedItem: Record<string, unknown> = {};
 for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
 if (field in item) {
 projectedItem[field] = item[field];
 }
 }

 const result = asRecord(item.result);
 if (result) {
 const text = extractMcpResultText(result.content);
 const summary = text ? summarizeToolTextOutput(text) : null;
 projectedItem.result = {
 ...(summary ? { content: summary } : {}),
 // MCP signals tool-level failure on the result, not on `item.error`.
 ...(result.isError === true ? { isError: true } : {}),
 };
 }

 return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
 const lines: string[] = [];
 for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
 const payload = asRecord(activity.payload);
 const data = asRecord(payload?.data);
 if (!payload || !data || payload.itemType === "mcp_tool_call") {
 if (!payload || !data) {
 return activity;
 }

 const projectedData: Record<string, unknown> = {};
 const item = projectCommandData(data);
 const item =
 payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
 if (item) {
 projectedData.item = item;
 }
Expand Down

120 changes: 113 additions & 7 deletions
apps/server/test/ActivityPayloadProjection.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
 }),
 makeActivity("mcp", "mcp_tool_call", {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 server: "repository",
 tool: "search",
 arguments: { query: "activity projection" },
 aggregatedOutput: "mcp payload remains available",
 status: "completed",
 durationMs: 12,
 error: null,
 result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
 aggregatedOutput: "bulk that no client reads",
 },
 ignored: "MCP data is rendered verbatim",
 toolCallId: "tool-mcp",
 ignored: "top-level bulk",
 }),
 makeActivity("search", "web_search", {
 rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
 });
 });

 it("passes MCP tool data through unchanged", () => {
 expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
 it("keeps the MCP call descriptor and bounds its result", () => {
 const projected = projectActivityPayload(fixtures[4]!);

 expect(projected.payload).toEqual({
 itemType: "mcp_tool_call",
 title: "mcp_tool_call",
 detail: "mcp_tool_call detail",
 status: "completed",
 requestKind: "command",
 data: {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 tool: "search",
 server: "repository",
 status: "completed",
 arguments: { query: "activity projection" },
 error: null,
 durationMs: 12,
 result: { content: "first result line" },
 },
 toolCallId: "tool-mcp",
 },
 });
 });

 it("bounds a megabyte-scale MCP result", () => {
 const huge = makeActivity("mcp-huge", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: {
 content: [
 { type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
 { type: "text", text: "x".repeat(200_000) },
 ],
 },
 },
 });

 const projected = projectActivityPayload(huge);
 const projectedSize = JSON.stringify(projected.payload).length;

 expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
 expect(projectedSize).toBeLessThan(500);
 expect(projected.payload).toMatchObject({
 data: {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: { content: "pull request body" },
 },
 },
 });
 });

 it("keeps a failing MCP call's error and isError flag", () => {
 const failed = makeActivity("mcp-error", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 status: "failed",
 error: { message: "not found", code: 404 },
 result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
 },
 });

 expect(projectActivityPayload(failed).payload).toMatchObject({
 data: {
 item: {
 error: { message: "not found", code: 404 },
 result: { content: "HTTP 404", isError: true },
 },
 },
 });
 });

 it("keeps in-flight MCP calls renderable without a result", () => {
 const started: OrchestrationThreadActivity = {
 ...makeActivity("mcp-started", "mcp_tool_call", {
 item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
 }),
 kind: "tool.started",
 };

 const projected = projectActivityPayload(started);
 const data = (projected.payload as { data: Record<string, unknown> }).data;

 // The clients gate the expanded body on `data.item !== undefined`.
 expect(data.item).toEqual({
 server: "github",
 tool: "fetch_pr",
 arguments: {},
 status: "inProgress",
 });
 });

 it("keeps current web and mobile derived output identical for every tool item type", () => {
 for (const activity of fixtures) {
 it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
 for (const activity of fixtures.filter(
 (fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
 )) {
 const projected = projectActivityPayload(activity);
 expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
 expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
 snapshotSequence: 7,
 thread: makeThread([fixtures[4]!]),
 });
 expect(projected.thread.activities).toEqual([fixtures[4]]);
 expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
 });

 it("does not filter live activity-appended events", () => {
Expand Down
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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fix(server): bound mcp tool payloads on the wire#5481

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privacy statement. We’ll occasionally send you account related emails.

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 Closed

t3dotgg
wants to merge
1
commit into

from

 Closed


fix(server): bound mcp tool payloads on the wire
#5481
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88 changes: 86 additions & 2 deletions
apps/server/src/orchestration/ActivityPayloadProjection.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -104,6 +104,89 @@ function projectCommandData(data: Record<string, unknown>): Record<string, unkno
 return Object.keys(projectedItem).length > 0 ? projectedItem : undefined;
}

/**
 * Fields of an MCP tool call item worth shipping: everything that describes
 * the call itself. `result` is handled separately because it carries the
 * unbounded tool output.
 */
const MCP_ITEM_DESCRIPTOR_FIELDS = [
 "type",
 "id",
 "tool",
 "server",
 "status",
 "arguments",
 "appContext",
 "error",
 "durationMs",
] as const;

/** Cap on the text handed to the summarizer — results reach megabytes. */
const MCP_RESULT_TEXT_LIMIT = 4_096;

/**
 * MCP results carry their payload in `result.content`, either as a plain
 * string or as the MCP content-block array (`[{ type: "text", text }, …]`).
 * Flattens the leading text so the shared tool-output summarizer can bound it.
 */
function extractMcpResultText(content: unknown): string | null {
 if (typeof content === "string") {
 return asTrimmedString(content.slice(0, MCP_RESULT_TEXT_LIMIT));
 }
 if (!Array.isArray(content)) {
 return null;
 }
 let joined = "";
 for (const block of content) {
 const text = asTrimmedString(asRecord(block)?.text);
 if (!text) {
 continue;
 }
 joined = joined.length > 0 ? `${joined}\n${text}` : text;
 if (joined.length >= MCP_RESULT_TEXT_LIMIT) {
 break;
 }
 }
 return asTrimmedString(joined.slice(0, MCP_RESULT_TEXT_LIMIT));
}

/**
 * Bounds an MCP tool call item for the wire. Both clients render `data.item`
 * as JSON in the expanded work-log row, so the call descriptor stays intact
 * while `result` — which carries the whole tool result, routinely a megabyte
 * for connector fetches — collapses to the same one-line preview regular tool
 * output gets. An item record always projects to a record so the clients'
 * `data.item !== undefined` check keeps holding.
 */
function projectMcpToolCallData(
 data: Record<string, unknown>,
): Record<string, unknown> | undefined {
 const item = asRecord(data.item);
 if (!item) {
 return undefined;
 }

 const projectedItem: Record<string, unknown> = {};
 for (const field of MCP_ITEM_DESCRIPTOR_FIELDS) {
 if (field in item) {
 projectedItem[field] = item[field];
 }
 }

 const result = asRecord(item.result);
 if (result) {
 const text = extractMcpResultText(result.content);
 const summary = text ? summarizeToolTextOutput(text) : null;
 projectedItem.result = {
 ...(summary ? { content: summary } : {}),
 // MCP signals tool-level failure on the result, not on `item.error`.
 ...(result.isError === true ? { isError: true } : {}),
 };
 }

 return projectedItem;
}

function summarizeToolTextOutput(value: string): string | null {
 const lines: string[] = [];
 for (const rawLine of value.split(/\r?\n/u)) {
Expand DownExpand Up@@ -160,12 +243,13 @@ export function projectActivityPayload(
): OrchestrationThreadActivity {
 const payload = asRecord(activity.payload);
 const data = asRecord(payload?.data);
 if (!payload || !data || payload.itemType === "mcp_tool_call") {
 if (!payload || !data) {
 return activity;
 }

 const projectedData: Record<string, unknown> = {};
 const item = projectCommandData(data);
 const item =
 payload.itemType === "mcp_tool_call" ? projectMcpToolCallData(data) : projectCommandData(data);
 if (item) {
 projectedData.item = item;
 }
Expand Down

120 changes: 113 additions & 7 deletions
apps/server/test/ActivityPayloadProjection.test.ts

View file


Open in desktop

Original file line numberDiff line numberDiff line change
Expand Up@@ -114,12 +114,19 @@ const fixtures = [
 }),
 makeActivity("mcp", "mcp_tool_call", {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 server: "repository",
 tool: "search",
 arguments: { query: "activity projection" },
 aggregatedOutput: "mcp payload remains available",
 status: "completed",
 durationMs: 12,
 error: null,
 result: { content: [{ type: "text", text: "first result line\nsecond result line" }] },
 aggregatedOutput: "bulk that no client reads",
 },
 ignored: "MCP data is rendered verbatim",
 toolCallId: "tool-mcp",
 ignored: "top-level bulk",
 }),
 makeActivity("search", "web_search", {
 rawOutput: {
Expand DownExpand Up@@ -184,12 +191,111 @@ describe("projectActivityPayload", () => {
 });
 });

 it("passes MCP tool data through unchanged", () => {
 expect(projectActivityPayload(fixtures[4]!)).toBe(fixtures[4]);
 it("keeps the MCP call descriptor and bounds its result", () => {
 const projected = projectActivityPayload(fixtures[4]!);

 expect(projected.payload).toEqual({
 itemType: "mcp_tool_call",
 title: "mcp_tool_call",
 detail: "mcp_tool_call detail",
 status: "completed",
 requestKind: "command",
 data: {
 item: {
 type: "mcpToolCall",
 id: "mcp_1",
 tool: "search",
 server: "repository",
 status: "completed",
 arguments: { query: "activity projection" },
 error: null,
 durationMs: 12,
 result: { content: "first result line" },
 },
 toolCallId: "tool-mcp",
 },
 });
 });

 it("bounds a megabyte-scale MCP result", () => {
 const huge = makeActivity("mcp-huge", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: {
 content: [
 { type: "text", text: `pull request body\n${"diff line\n".repeat(120_000)}` },
 { type: "text", text: "x".repeat(200_000) },
 ],
 },
 },
 });

 const projected = projectActivityPayload(huge);
 const projectedSize = JSON.stringify(projected.payload).length;

 expect(JSON.stringify(huge.payload).length).toBeGreaterThan(1_000_000);
 expect(projectedSize).toBeLessThan(500);
 expect(projected.payload).toMatchObject({
 data: {
 item: {
 server: "github",
 tool: "fetch_pr",
 arguments: { number: 5219 },
 status: "completed",
 result: { content: "pull request body" },
 },
 },
 });
 });

 it("keeps a failing MCP call's error and isError flag", () => {
 const failed = makeActivity("mcp-error", "mcp_tool_call", {
 item: {
 server: "github",
 tool: "fetch_pr",
 status: "failed",
 error: { message: "not found", code: 404 },
 result: { isError: true, content: [{ type: "text", text: "HTTP 404" }] },
 },
 });

 expect(projectActivityPayload(failed).payload).toMatchObject({
 data: {
 item: {
 error: { message: "not found", code: 404 },
 result: { content: "HTTP 404", isError: true },
 },
 },
 });
 });

 it("keeps in-flight MCP calls renderable without a result", () => {
 const started: OrchestrationThreadActivity = {
 ...makeActivity("mcp-started", "mcp_tool_call", {
 item: { server: "github", tool: "fetch_pr", arguments: {}, status: "inProgress" },
 }),
 kind: "tool.started",
 };

 const projected = projectActivityPayload(started);
 const data = (projected.payload as { data: Record<string, unknown> }).data;

 // The clients gate the expanded body on `data.item !== undefined`.
 expect(data.item).toEqual({
 server: "github",
 tool: "fetch_pr",
 arguments: {},
 status: "inProgress",
 });
 });

 it("keeps current web and mobile derived output identical for every tool item type", () => {
 for (const activity of fixtures) {
 it("keeps current web and mobile derived output identical for every non-MCP tool item type", () => {
 for (const activity of fixtures.filter(
 (fixture) => (fixture.payload as { itemType: string }).itemType !== "mcp_tool_call",
 )) {
 const projected = projectActivityPayload(activity);
 expect(deriveWorkLogEntries([projected])).toEqual(deriveWorkLogEntries([activity]));
 expect(comparableThreadFeed([projected])).toEqual(comparableThreadFeed([activity]));
Expand DownExpand Up@@ -333,7 +439,7 @@ describe("context-window snapshot dedup", () => {
 snapshotSequence: 7,
 thread: makeThread([fixtures[4]!]),
 });
 expect(projected.thread.activities).toEqual([fixtures[4]]);
 expect(projected.thread.activities).toEqual([projectActivityPayload(fixtures[4]!)]);
 });

 it("does not filter live activity-appended events", () => {
Expand Down
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