Skip to content

fix: throw ProtocolError as JSON-RPC error for tool not found #1567

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
stakeswky wants to merge 3 commits into from
+19 −26
Closed

fix: throw ProtocolError as JSON-RPC error for tool not found #1567

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
1030c40
fix: throw ProtocolError as JSON-RPC error for tool not found
Feb 22, 2026
6b9d050
fix: move tool lookup errors outside try-catch to preserve validation…
Feb 26, 2026
8178fb0
style: fix prettier formatting in mcp.ts
Feb 26, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
17 changes: 9 additions & 8 deletions packages/server/src/server/mcp.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -166,15 +166,16 @@ export class McpServer {
);

this.server.setRequestHandler('tools/call', async (request, ctx): Promise<CallToolResult | CreateTaskResult> => {
try {
const tool = this._registeredTools[request.params.name];
if (!tool) {
throw new ProtocolError(ProtocolErrorCode.InvalidParams, `Tool ${request.params.name} not found`);
}
if (!tool.enabled) {
throw new ProtocolError(ProtocolErrorCode.InvalidParams, `Tool ${request.params.name} disabled`);
}
// Tool lookup errors are JSON-RPC errors, not tool errors
const tool = this._registeredTools[request.params.name];
if (!tool) {
throw new ProtocolError(ProtocolErrorCode.InvalidParams, `Tool ${request.params.name} not found`);
}
if (!tool.enabled) {
throw new ProtocolError(ProtocolErrorCode.InvalidParams, `Tool ${request.params.name} disabled`);
}

try {
const isTaskRequest = !!request.params.task;
const taskSupport = tool.execution?.taskSupport;
const isTaskHandler = 'createTask' in (tool.handler as AnyToolHandler<AnySchema>);
Expand Down
28 changes: 10 additions & 18 deletions test/integration/test/server/mcp.test.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1837,25 +1837,17 @@ describe('Zod v4', () => {

await Promise.all([client.connect(clientTransport), mcpServer.server.connect(serverTransport)]);

const result = await client.request(
{
method: 'tools/call',
params: {
name: 'nonexistent-tool'
}
},
CallToolResultSchema
);

expect(result.isError).toBe(true);
expect(result.content).toEqual(
expect.arrayContaining([
await expect(
client.request(
{
type: 'text',
text: expect.stringContaining('Tool nonexistent-tool not found')
}
])
);
method: 'tools/call',
params: {
name: 'nonexistent-tool'
}
},
CallToolResultSchema
)
).rejects.toThrow(/Tool nonexistent-tool not found/);
});

/***
Expand Down
Loading