Skip to content

tokio task not closed at shutdown #220

Closed
#280
Closed
tokio task not closed at shutdown#220
#280
Assignees
4t145
Labels
T-bugBug fixes and error corrections
Milestone
Pre release milestones

Description

@3DRaven
3DRaven
opened on May 25, 2025

Describe the bug
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.

To Reproduce

  1. Attached full project example with the problem. mcp-problem-example.zip
  2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
    As example integration with cursor IDE
{
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
  1. Run in terminal tokio-console https://crates.io/crates/tokio-console
  2. Disconnect/Turn off from the MCP server in client (IDE or inspector)

Expected behavior
After stopping the MCP server, the process should be terminated.

Logs
All code has finished executing, but the task remains unclosed.

2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message

Final message indicates the last log entry generated by the logger.

Additional context
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:

ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

tokio-console shows the issue — a task is not properly terminated.:

30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

Metadata

Metadata

Assignees

Labels

T-bugBug fixes and error corrections

Type

No type

Projects

No projects

    Milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions

    , 'i'); if (__m === '*' || __re.test(location.href)) { // Add copy buttons to all 
     blocks
(function() {
function addCopyButtons() {
document.querySelectorAll('pre code').forEach(function(codeBlock) {
if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;
codeBlock.parentElement.setAttribute('data-copy-added', 'true');
var btn = document.createElement('button');
btn.textContent = 'Copy';
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;';
btn.onmouseover = function() { this.style.opacity = '1'; };
btn.onmouseout = function() { this.style.opacity = '0.7'; };
btn.onclick = function() {
navigator.clipboard.writeText(codeBlock.textContent).then(function() {
btn.textContent = 'Copied!';
setTimeout(function() { btn.textContent = 'Copy'; }, 1500);
});
};
codeBlock.parentElement.style.position = 'relative';
codeBlock.parentElement.appendChild(btn);
});
}
addCopyButtons();
// Re-run on dynamic content
var observer = new MutationObserver(addCopyButtons);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
tokio task not closed at shutdown · Issue #220 · modelcontextprotocol/rust-sdk · GitHub
    Skip to content
    tokio task not closed at shutdown #220
    Closed
    #280
    Closed
    tokio task not closed at shutdown#220
    #280
    Assignees
    4t145
    Labels
    T-bugBug fixes and error corrections
    Milestone
    Pre release milestones
    Description
    @3DRaven
    3DRaven
    opened on May 25, 2025
    Describe the bug
    
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.
    To Reproduce
    1. Attached full project example with the problem. mcp-problem-example.zip
    2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
      
As example integration with cursor IDE
    {
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
    1. Run in terminal tokio-console https://crates.io/crates/tokio-console
    2. Disconnect/Turn off from the MCP server in client (IDE or inspector)
    Expected behavior
    
After stopping the MCP server, the process should be terminated.
    Logs
    
All code has finished executing, but the task remains unclosed.
    2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message 
    Final message indicates the last log entry generated by the logger.
    Additional context
    
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:
    ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

    tokio-console shows the issue — a task is not properly terminated.:
    30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

    Metadata
    Metadata
    Assignees
    Labels
    T-bugBug fixes and error corrections
    Type
    No type
    Projects
    No projects
      Milestone
      Relationships
      None yet
      Development
      No branches or pull requests
      Issue actions
      
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
.markdown-body pre { background: #161b22 !important; }
.markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }
.markdown-body table th, .markdown-body table td { border-color: #30363d !important; }
.markdown-body img { background: #0d1117; }
.markdown-body blockquote { border-left-color: #8b949e; }
.markdown-body hr { border-color: #30363d; }
';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
tokio task not closed at shutdown · Issue #220 · modelcontextprotocol/rust-sdk · GitHub
      Skip to content
      tokio task not closed at shutdown #220
      Closed
      #280
      Closed
      tokio task not closed at shutdown#220
      #280
      Assignees
      4t145
      Labels
      T-bugBug fixes and error corrections
      Milestone
      Pre release milestones
      Description
      @3DRaven
      3DRaven
      opened on May 25, 2025
      Describe the bug
      
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.
      To Reproduce
      1. Attached full project example with the problem. mcp-problem-example.zip
      2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
        
As example integration with cursor IDE
      {
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
      1. Run in terminal tokio-console https://crates.io/crates/tokio-console
      2. Disconnect/Turn off from the MCP server in client (IDE or inspector)
      Expected behavior
      
After stopping the MCP server, the process should be terminated.
      Logs
      
All code has finished executing, but the task remains unclosed.
      2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message 
      Final message indicates the last log entry generated by the logger.
      Additional context
      
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:
      ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

      tokio-console shows the issue — a task is not properly terminated.:
      30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

      Metadata
      Metadata
      Assignees
      Labels
      T-bugBug fixes and error corrections
      Type
      No type
      Projects
      No projects
        Milestone
        Relationships
        None yet
        Development
        No branches or pull requests
        Issue actions
        
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
var style = document.createElement('style');
style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
if (regex.test(text)) {
found = true;
var frag = document.createDocumentFragment();
var parts = text.split(regex);
parts.forEach(function(part, i) {
if (i % 2 === 0) {
frag.appendChild(document.createTextNode(part));
} else {
var span = document.createElement('span');
span.className = 'userscript-highlight';
span.textContent = part;
frag.appendChild(span);
}
});
node.parentNode.replaceChild(frag, node);
}
});
} else if (node.nodeType === 1 && node.childNodes) { // element
var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];
if (!skipTags.includes(node.tagName)) {
Array.from(node.childNodes).forEach(highlight);
}
}
}
highlight(document.body);
// Re-highlight on dynamic content
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1 || node.nodeType === 3) highlight(node);
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
tokio task not closed at shutdown · Issue #220 · modelcontextprotocol/rust-sdk · GitHub
        Skip to content
        tokio task not closed at shutdown #220
        Closed
        #280
        Closed
        tokio task not closed at shutdown#220
        #280
        Assignees
        4t145
        Labels
        T-bugBug fixes and error corrections
        Milestone
        Pre release milestones
        Description
        @3DRaven
        3DRaven
        opened on May 25, 2025
        Describe the bug
        
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.
        To Reproduce
        1. Attached full project example with the problem. mcp-problem-example.zip
        2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
          
As example integration with cursor IDE
        {
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
        1. Run in terminal tokio-console https://crates.io/crates/tokio-console
        2. Disconnect/Turn off from the MCP server in client (IDE or inspector)
        Expected behavior
        
After stopping the MCP server, the process should be terminated.
        Logs
        
All code has finished executing, but the task remains unclosed.
        2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message 
        Final message indicates the last log entry generated by the logger.
        Additional context
        
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:
        ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

        tokio-console shows the issue — a task is not properly terminated.:
        30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

        Metadata
        Metadata
        Assignees
        Labels
        T-bugBug fixes and error corrections
        Type
        No type
        Projects
        No projects
          Milestone
          Relationships
          None yet
          Development
          No branches or pull requests
          Issue actions
          
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
var observer = new MutationObserver(function(mutations) {
mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
tokio task not closed at shutdown · Issue #220 · modelcontextprotocol/rust-sdk · GitHub
          Skip to content
          tokio task not closed at shutdown #220
          Closed
          #280
          Closed
          tokio task not closed at shutdown#220
          #280
          Assignees
          4t145
          Labels
          T-bugBug fixes and error corrections
          Milestone
          Pre release milestones
          Description
          @3DRaven
          3DRaven
          opened on May 25, 2025
          Describe the bug
          
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.
          To Reproduce
          1. Attached full project example with the problem. mcp-problem-example.zip
          2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
            
As example integration with cursor IDE
          {
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
          1. Run in terminal tokio-console https://crates.io/crates/tokio-console
          2. Disconnect/Turn off from the MCP server in client (IDE or inspector)
          Expected behavior
          
After stopping the MCP server, the process should be terminated.
          Logs
          
All code has finished executing, but the task remains unclosed.
          2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message 
          Final message indicates the last log entry generated by the logger.
          Additional context
          
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:
          ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

          tokio-console shows the issue — a task is not properly terminated.:
          30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

          Metadata
          Metadata
          Assignees
          Labels
          T-bugBug fixes and error corrections
          Type
          No type
          Projects
          No projects
            Milestone
            Relationships
            None yet
            Development
            No branches or pull requests
            Issue actions
            
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
tokio task not closed at shutdown · Issue #220 · modelcontextprotocol/rust-sdk · GitHub
            Skip to content
            tokio task not closed at shutdown #220
            Closed
            #280
            Closed
            tokio task not closed at shutdown#220
            #280
            Assignees
            4t145
            Labels
            T-bugBug fixes and error corrections
            Milestone
            Pre release milestones
            Description
            @3DRaven
            3DRaven
            opened on May 25, 2025
            Describe the bug
            
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.
            To Reproduce
            1. Attached full project example with the problem. mcp-problem-example.zip
            2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
              
As example integration with cursor IDE
            {
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
            1. Run in terminal tokio-console https://crates.io/crates/tokio-console
            2. Disconnect/Turn off from the MCP server in client (IDE or inspector)
            Expected behavior
            
After stopping the MCP server, the process should be terminated.
            Logs
            
All code has finished executing, but the task remains unclosed.
            2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message 
            Final message indicates the last log entry generated by the logger.
            Additional context
            
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:
            ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

            tokio-console shows the issue — a task is not properly terminated.:
            30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

            Metadata
            Metadata
            Assignees
            Labels
            T-bugBug fixes and error corrections
            Type
            No type
            Projects
            No projects
              Milestone
              Relationships
              None yet
              Development
              No branches or pull requests
              Issue actions
              
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
tokio task not closed at shutdown · Issue #220 · modelcontextprotocol/rust-sdk · GitHub
              Skip to content
              tokio task not closed at shutdown #220
              Closed
              #280
              Closed
              tokio task not closed at shutdown#220
              #280
              Assignees
              4t145
              Labels
              T-bugBug fixes and error corrections
              Milestone
              Pre release milestones
              Description
              @3DRaven
              3DRaven
              opened on May 25, 2025
              Describe the bug
              
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.
              To Reproduce
              1. Attached full project example with the problem. mcp-problem-example.zip
              2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
                
As example integration with cursor IDE
              {
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
              1. Run in terminal tokio-console https://crates.io/crates/tokio-console
              2. Disconnect/Turn off from the MCP server in client (IDE or inspector)
              Expected behavior
              
After stopping the MCP server, the process should be terminated.
              Logs
              
All code has finished executing, but the task remains unclosed.
              2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message 
              Final message indicates the last log entry generated by the logger.
              Additional context
              
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:
              ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

              tokio-console shows the issue — a task is not properly terminated.:
              30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

              Metadata
              Metadata
              Assignees
              Labels
              T-bugBug fixes and error corrections
              Type
              No type
              Projects
              No projects
                Milestone
                Relationships
                None yet
                Development
                No branches or pull requests
                Issue actions
                
, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
tokio task not closed at shutdown · Issue #220 · modelcontextprotocol/rust-sdk · GitHub
                Skip to content
                tokio task not closed at shutdown #220
                Closed
                #280
                Closed
                tokio task not closed at shutdown#220
                #280
                Assignees
                4t145
                Labels
                T-bugBug fixes and error corrections
                Milestone
                Pre release milestones
                Description
                @3DRaven
                3DRaven
                opened on May 25, 2025
                Describe the bug
                
When performing a graceful shutdown with a Tokio cancellation token, the task that reads from stdin does not terminate properly, causing the process to remain running.
                To Reproduce
                1. Attached full project example with the problem. mcp-problem-example.zip
                2. Add integration with this MCP server to MCP inspector or cursor IDE with stdio transport.
                  
As example integration with cursor IDE
                {
"mcpServers": {
"mcp-problem-example": {
"command": "sh",
"args": [
"path/to/mcp-problem-example/start.sh"
],
"env": []
},
}
                1. Run in terminal tokio-console https://crates.io/crates/tokio-console
                2. Disconnect/Turn off from the MCP server in client (IDE or inspector)
                Expected behavior
                
After stopping the MCP server, the process should be terminated.
                Logs
                
All code has finished executing, but the task remains unclosed.
                2025-05-25T13:24:17.338Z INFO mcp_problem_example: Tracing initialized successfully
2025-05-25T13:24:17.338Z INFO mcp_problem_example: Starting server in work directory: example/mcp-problem-example 2025-05-25T13:24:17.340Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: Starting MCP service
2025-05-25T13:24:17.341Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}:serve_inner: rmcp::service: Service initialized as server peer_info=InitializeRequestParam { protocol_version: ProtocolVersion("2024-11-05"), capabilities: ClientCapabilities { experimental: None, roots: Some(RootsCapabilities { list_changed: Some(false) }), sampling: None }, client_info: Implementation { name: "cursor-vscode", version: "1.0.0" } }
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server initialized
2025-05-25T13:24:17.342Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=PeerMessage(Request(ListToolsRequest(Request { method: ListToolsRequestMethod, params: None }), Number(1)))
2025-05-25T13:24:17.342Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: received request id=1 request=ListToolsRequest(Request { method: ListToolsRequestMethod, params: None })
2025-05-25T13:24:17.343Z INFO runtime.spawn{kind=task task.name= task.id=32 size.bytes=1168 loc.file="/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=604 loc.col=25}: rmcp::service: response message id=1 result=ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] })
2025-05-25T13:24:17.344Z DEBUG runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: new event evt=ToSink(Response(ListToolsResult(ListToolsResult { next_cursor: None, tools: [Tool { name: "search_implemented", description: "Search for implemented symbols in the project", input_schema: {"$schema": String("http://json-schema.org/draft-07/schema#"), "properties": Object {"first": Object {"items": Object {"type": String("string")}, "type": String("array")}, "second": Object {"items": Object {"type": String("string")}, "type": String("array")}}, "required": Array [String("first"), String("second")], "title": String("McpRequest"), "type": String("object")} }] }), Number(1)))
2025-05-25T13:24:30.801Z DEBUG runtime.spawn{kind=task task.name= task.id=23 size.bytes=160 loc.file="src/main.rs" loc.line=21 loc.col=6}: tokio_graceful_shutdown::signal_handling: Received SIGTERM.
2025-05-25T13:24:30.802Z INFO tokio_graceful_shutdown::toplevel: Shutting down ...
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: task cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=30 size.bytes=928 loc.file="~/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/rmcp-0.1.5/src/service.rs" loc.line=495 loc.col=18}: rmcp::service: serve finished quit_reason=Cancelled
2025-05-25T13:24:30.802Z INFO runtime.spawn{kind=task task.name= task.id=24 size.bytes=1336 loc.file="src/main.rs" loc.line=17 loc.col=11}: mcp_problem_example: MCP server shutdown with reason: Cancelled
2025-05-25T13:24:30.803Z INFO tokio_graceful_shutdown::toplevel: Shutdown finished.
2025-05-25T13:24:30.803Z INFO mcp_problem_example: Finall message 
                Final message indicates the last log entry generated by the logger.
                Additional context
                
The previous process is not terminated properly, so each rerun spawns an additional process that continues running in the background:
                ps -A|grep mcp
880290 ? 00:00:00 mcp-problem-exa
889850 ? 00:00:00 mcp-problem-exa

                tokio-console shows the issue — a task is not properly terminated.:
                30 ⏫ 8m15s 2ms 8m02s 13s 6 task <cargo>/rmcp-0.1.5/src/service.rs:495:18 size.bytes=928 target=tokio::task │
33 ▶ 8m15s 8m15s 0ns 131µs 1 blocking <cargo>/tokio-1.45.1/src/io/blocking.rs:76:46 fn=<tokio::io::blocking::Blocking<std::io::stdio::Stdin>

                Metadata
                Metadata
                Assignees
                Labels
                T-bugBug fixes and error corrections
                Type
                No type
                Projects
                No projects
                  Milestone
                  Relationships
                  None yet
                  Development
                  No branches or pull requests
                  Issue actions