single tool for normal and error path

2026-04-17 15:43:24 +02:00 · 2026-02-19 21:17:52 +00:00
parent b69e0778c8
commit 41bcddcbdf
8 changed files with 1418 additions and 196 deletions
--- a/src/everything/tests/registrations.test.ts
+++ b/src/everything/tests/registrations.test.ts
@@ -67,16 +67,15 @@ describe('Registration Index Files', () => {

      registerConditionalTools(mockServerWithCapabilities);

-      // Should register 5 conditional tools + 3 task-based tools when all capabilities present
-      expect(mockServerWithCapabilities.registerTool).toHaveBeenCalledTimes(5);
+      // Should register 4 conditional tools + 3 task-based tools when all capabilities present
+      expect(mockServerWithCapabilities.registerTool).toHaveBeenCalledTimes(4);

      const registeredTools = (
        mockServerWithCapabilities.registerTool as any
      ).mock.calls.map((call: any[]) => call[0]);
      expect(registeredTools).toContain('get-roots-list');
      expect(registeredTools).toContain('trigger-elicitation-request');
-      expect(registeredTools).toContain('trigger-url-elicitation-request');
-      expect(registeredTools).toContain('trigger-url-elicitation-required-error');
+      expect(registeredTools).toContain('trigger-url-elicitation');
      expect(registeredTools).toContain('trigger-sampling-request');

      // Task-based tools are registered via experimental.tasks.registerToolTask
--- a/src/everything/tests/tools.test.ts
+++ b/src/everything/tests/tools.test.ts
@@ -13,8 +13,7 @@ import { registerToggleSimulatedLoggingTool } from '../tools/toggle-simulated-lo
 import { registerToggleSubscriberUpdatesTool } from '../tools/toggle-subscriber-updates.js';
 import { registerTriggerSamplingRequestTool } from '../tools/trigger-sampling-request.js';
 import { registerTriggerElicitationRequestTool } from '../tools/trigger-elicitation-request.js';
-import { registerTriggerUrlElicitationRequestTool } from '../tools/trigger-url-elicitation-request.js';
-import { registerTriggerUrlElicitationRequiredErrorTool } from '../tools/trigger-url-elicitation-required-error.js';
+import { registerTriggerUrlElicitationTool } from '../tools/trigger-url-elicitation.js';
 import { registerGetRootsListTool } from '../tools/get-roots-list.js';
 import { registerGZipFileAsResourceTool } from '../tools/gzip-file-as-resource.js';

@@ -708,7 +707,7 @@ describe('Tools', () => {
    });
  });

-  describe('trigger-url-elicitation-request', () => {
+  describe('trigger-url-elicitation', () => {
    it('should not register when client does not support URL elicitation', () => {
      const handlers: Map<string, Function> = new Map();
      const mockServer = {
@@ -720,7 +719,7 @@ describe('Tools', () => {
        },
      } as unknown as McpServer;

-      registerTriggerUrlElicitationRequestTool(mockServer);
+      registerTriggerUrlElicitationTool(mockServer);

      expect(mockServer.registerTool).not.toHaveBeenCalled();
    });
@@ -733,28 +732,26 @@ describe('Tools', () => {
        }),
        server: {
          getClientCapabilities: vi.fn(() => ({ elicitation: { url: {} } })),
-          createElicitationCompletionNotifier: vi.fn(() => vi.fn()),
        },
      } as unknown as McpServer;

-      registerTriggerUrlElicitationRequestTool(mockServer);
+      registerTriggerUrlElicitationTool(mockServer);

      expect(mockServer.registerTool).toHaveBeenCalledWith(
-        'trigger-url-elicitation-request',
+        'trigger-url-elicitation',
        expect.objectContaining({
-          title: 'Trigger URL Elicitation Request Tool',
+          title: 'Trigger URL Elicitation Tool',
          description: expect.stringContaining('URL elicitation'),
        }),
        expect.any(Function)
      );
    });

-    it('should send URL-mode elicitation request and notify completion when requested', async () => {
+    it('should send URL-mode elicitation request when errorPath is false', async () => {
      const handlers: Map<string, Function> = new Map();
      const mockSendRequest = vi.fn().mockResolvedValue({
        action: 'accept',
      });
-      const mockNotifyComplete = vi.fn().mockResolvedValue(undefined);

      const mockServer = {
        registerTool: vi.fn((name: string, config: any, handler: Function) => {
@@ -762,21 +759,18 @@ describe('Tools', () => {
        }),
        server: {
          getClientCapabilities: vi.fn(() => ({ elicitation: { url: {} } })),
-          createElicitationCompletionNotifier: vi
-            .fn()
-            .mockReturnValue(mockNotifyComplete),
        },
      } as unknown as McpServer;

-      registerTriggerUrlElicitationRequestTool(mockServer);
+      registerTriggerUrlElicitationTool(mockServer);

-      const handler = handlers.get('trigger-url-elicitation-request')!;
+      const handler = handlers.get('trigger-url-elicitation')!;
      const result = await handler(
        {
          url: 'https://example.com/verify',
          message: 'Open this page to verify your identity',
          elicitationId: 'elicitation-123',
-          sendCompletionNotification: true,
+          errorPath: false,
        },
        { sendRequest: mockSendRequest }
      );
@@ -795,32 +789,10 @@ describe('Tools', () => {
        expect.anything()
      );

-      expect(mockServer.server.createElicitationCompletionNotifier).toHaveBeenCalledWith(
-        'elicitation-123'
-      );
-      expect(mockNotifyComplete).toHaveBeenCalledTimes(1);
      expect(result.content[0].text).toContain('URL elicitation action: accept');
    });
-  });

-  describe('trigger-url-elicitation-required-error', () => {
-    it('should not register when client does not support URL elicitation', () => {
-      const handlers: Map<string, Function> = new Map();
-      const mockServer = {
-        registerTool: vi.fn((name: string, config: any, handler: Function) => {
-          handlers.set(name, handler);
-        }),
-        server: {
-          getClientCapabilities: vi.fn(() => ({ elicitation: { form: {} } })),
-        },
-      } as unknown as McpServer;
-
-      registerTriggerUrlElicitationRequiredErrorTool(mockServer);
-
-      expect(mockServer.registerTool).not.toHaveBeenCalled();
-    });
-
-    it('should register when client supports URL elicitation', () => {
+    it('should throw MCP error -32042 with required URL elicitation data when errorPath is true', async () => {
      const handlers: Map<string, Function> = new Map();
      const mockServer = {
        registerTool: vi.fn((name: string, config: any, handler: Function) => {
@@ -831,40 +803,22 @@ describe('Tools', () => {
        },
      } as unknown as McpServer;

-      registerTriggerUrlElicitationRequiredErrorTool(mockServer);
+      registerTriggerUrlElicitationTool(mockServer);

-      expect(mockServer.registerTool).toHaveBeenCalledWith(
-        'trigger-url-elicitation-required-error',
-        expect.objectContaining({
-          title: 'Trigger URL Elicitation Required Error Tool',
-        }),
-        expect.any(Function)
-      );
-    });
-
-    it('should throw MCP error -32042 with required URL elicitation data', async () => {
-      const handlers: Map<string, Function> = new Map();
-      const mockServer = {
-        registerTool: vi.fn((name: string, config: any, handler: Function) => {
-          handlers.set(name, handler);
-        }),
-        server: {
-          getClientCapabilities: vi.fn(() => ({ elicitation: { url: {} } })),
-        },
-      } as unknown as McpServer;
-
-      registerTriggerUrlElicitationRequiredErrorTool(mockServer);
-
-      const handler = handlers.get('trigger-url-elicitation-required-error')!;
+      const handler = handlers.get('trigger-url-elicitation')!;

      expect.assertions(2);

      try {
-        await handler({
-          url: 'https://example.com/connect',
-          message: 'Authorization is required to continue.',
-          elicitationId: 'elicitation-xyz',
-        });
+        await handler(
+          {
+            url: 'https://example.com/connect',
+            message: 'Authorization is required to continue.',
+            elicitationId: 'elicitation-xyz',
+            errorPath: true,
+          },
+          {}
+        );
      } catch (error: any) {
        expect(error.code).toBe(-32042);
        expect(error.data.elicitations[0]).toEqual({
--- a/src/everything/docs/features.md
+++ b/src/everything/docs/features.md
@@ -19,12 +19,11 @@
 - `get-structured-content` (tools/get-structured-content.ts): Demonstrates structured responses. Accepts `location` input and returns both backward‑compatible `content` (a `text` block containing JSON) and `structuredContent` validated by an `outputSchema` (temperature, conditions, humidity).
 - `get-sum` (tools/get-sum.ts): For two numbers `a` and `b` calculates and returns their sum. Uses Zod to validate inputs.
 - `get-tiny-image` (tools/get-tiny-image.ts): Returns a tiny PNG MCP logo as an `image` content item with brief descriptive text before and after.
- `trigger-long-running-operation` (tools/trigger-trigger-long-running-operation.ts): Simulates a multi-step operation over a given `duration` and number of `steps`; reports progress via `notifications/progress` when a `progressToken` is provided by the client.
+- `trigger-long-running-operation` (tools/trigger-long-running-operation.ts): Simulates a multi-step operation over a given `duration` and number of `steps`; reports progress via `notifications/progress` when a `progressToken` is provided by the client.
 - `toggle-simulated-logging` (tools/toggle-simulated-logging.ts): Starts or stops simulated, random‑leveled logging for the invoking session. Respects the client’s selected minimum logging level.
 - `toggle-subscriber-updates` (tools/toggle-subscriber-updates.ts): Starts or stops simulated resource update notifications for URIs the invoking session has subscribed to.
 - `trigger-elicitation-request` (tools/trigger-elicitation-request.ts): Issues an `elicitation/create` request using form-mode fields (strings, numbers, booleans, enums, and format validation) and returns the resulting action/content.
- `trigger-url-elicitation-request` (tools/trigger-url-elicitation-request.ts): Issues an `elicitation/create` request in URL mode (`mode: "url"`) with an `elicitationId`, and can optionally emit `notifications/elicitation/complete` after acceptance. Requires client capability `elicitation.url`.
- `trigger-url-elicitation-required-error` (tools/trigger-url-elicitation-required-error.ts): Throws MCP error `-32042` (`UrlElicitationRequiredError`) with one or more required URL-mode elicitations in `error.data.elicitations`, demonstrating the retry-after-elicitation flow.
+- `trigger-url-elicitation` (tools/trigger-url-elicitation.ts): Issues an `elicitation/create` request in URL mode (`mode: "url"`) with an `elicitationId`, or throws MCP error `-32042` (`UrlElicitationRequiredError`) when `errorPath=true`. Requires client capability `elicitation.url`.
 - `trigger-sampling-request` (tools/trigger-sampling-request.ts): Issues a `sampling/createMessage` request to the client/LLM using provided `prompt` and optional generation controls; returns the LLM's response payload.
 - `simulate-research-query` (tools/simulate-research-query.ts): Demonstrates MCP Tasks (SEP-1686) with a simulated multi-stage research operation. Accepts `topic` and `ambiguous` parameters. Returns a task that progresses through stages with status updates. If `ambiguous` is true and client supports elicitation, sends an elicitation request directly to gather clarification before completing.
 - `trigger-sampling-request-async` (tools/trigger-sampling-request-async.ts): Demonstrates bidirectional tasks where the server sends a sampling request that the client executes as a background task. Server polls for status and retrieves the LLM result when complete. Requires client to support `tasks.requests.sampling.createMessage`.
--- a/src/everything/docs/structure.md
+++ b/src/everything/docs/structure.md
@@ -48,13 +48,15 @@ src/everything
     │   ├── get-sum.ts
     │   ├── get-tiny-image.ts
     │   ├── gzip-file-as-resource.ts
+     │   ├── simulate-research-query.ts
     │   ├── toggle-simulated-logging.ts
     │   ├── toggle-subscriber-updates.ts
     │   ├── trigger-elicitation-request.ts
+     │   ├── trigger-elicitation-request-async.ts
     │   ├── trigger-long-running-operation.ts
-     │   ├── trigger-url-elicitation-required-error.ts
-     │   ├── trigger-url-elicitation-request.ts
-     │   └── trigger-sampling-request.ts
+     │   ├── trigger-sampling-request.ts
+     │   ├── trigger-sampling-request-async.ts
+     │   └── trigger-url-elicitation.ts
     └── transports
         ├── sse.ts
         ├── stdio.ts
@@ -84,8 +86,8 @@ src/everything

 - `architecture.md`
  - This document.
- `server-instructions.md`
-  - Human‑readable instructions intended to be passed to the client/LLM as for guidance on server use. Loaded by the server at startup and returned in the "initialize" exchange.
+- `instructions.md`
+  - Human‑readable instructions intended to be passed to the client/LLM as guidance on server use. Loaded by the server at startup and returned in the initialize exchange.

 ### `prompts/`

@@ -151,12 +153,16 @@ src/everything
    - `GZIP_ALLOWED_DOMAINS` (comma-separated allowlist; empty means all domains allowed)
 - `trigger-elicitation-request.ts`
  - Registers a `trigger-elicitation-request` tool that sends an `elicitation/create` request to the client/LLM and returns the elicitation result.
- `trigger-url-elicitation-request.ts`
-  - Registers a `trigger-url-elicitation-request` tool that sends an out-of-band URL-mode `elicitation/create` request (`mode: "url"`) including an `elicitationId`, and can optionally emit `notifications/elicitation/complete` after acceptance.
- `trigger-url-elicitation-required-error.ts`
-  - Registers a `trigger-url-elicitation-required-error` tool that throws MCP error `-32042` (`UrlElicitationRequiredError`) with required URL-mode elicitation params in `error.data.elicitations`.
+- `trigger-url-elicitation.ts`
+  - Registers a `trigger-url-elicitation` tool that either sends an out-of-band URL-mode `elicitation/create` request (`mode: "url"`) including an `elicitationId` (request path) or throws `UrlElicitationRequiredError` (`-32042`) for client-handled URL elicitation (error path).
 - `trigger-sampling-request.ts`
  - Registers a `trigger-sampling-request` tool that sends a `sampling/createMessage` request to the client/LLM and returns the sampling result.
+- `trigger-sampling-request-async.ts`
+  - Registers a `trigger-sampling-request-async` tool that demonstrates bidirectional tasks where the server sends a sampling request that the client executes asynchronously, then polls task status and fetches the result.
+- `trigger-elicitation-request-async.ts`
+  - Registers a `trigger-elicitation-request-async` tool that demonstrates bidirectional tasks where the server sends an elicitation request that the client executes asynchronously, then polls task status and fetches the result.
+- `simulate-research-query.ts`
+  - Registers a `simulate-research-query` tool that demonstrates server-side MCP Tasks with staged progress updates and optional elicitation for ambiguous queries.
 - `get-structured-content.ts`
  - Registers a `get-structured-content` tool that demonstrates structuredContent block responses.
 - `get-sum.ts`
@@ -164,7 +170,7 @@ src/everything
 - `get-tiny-image.ts`
  - Registers a `get-tiny-image` tool, which returns a tiny PNG MCP logo as an `image` content item, along with surrounding descriptive `text` items.
 - `trigger-long-running-operation.ts`
-  - Registers a `long-running-operation` tool that simulates a long-running task over a specified `duration` (seconds) and number of `steps`; emits `notifications/progress` updates when the client supplies a `progressToken`.
+  - Registers a `trigger-long-running-operation` tool that simulates a long-running task over a specified `duration` (seconds) and number of `steps`; emits `notifications/progress` updates when the client supplies a `progressToken`.
 - `toggle-simulated-logging.ts`
  - Registers a `toggle-simulated-logging` tool, which starts or stops simulated logging for the invoking session.
 - `toggle-subscriber-updates.ts`
--- a/src/everything/pnpm-lock.yaml
+++ b/src/everything/pnpm-lock.yaml
--- a/src/everything/tools/index.ts
+++ b/src/everything/tools/index.ts
@@ -17,8 +17,7 @@ import { registerTriggerSamplingRequestTool } from "./trigger-sampling-request.j
 import { registerTriggerSamplingRequestAsyncTool } from "./trigger-sampling-request-async.js";
 import { registerTriggerElicitationRequestAsyncTool } from "./trigger-elicitation-request-async.js";
 import { registerSimulateResearchQueryTool } from "./simulate-research-query.js";
-import { registerTriggerUrlElicitationRequestTool } from "./trigger-url-elicitation-request.js";
-import { registerTriggerUrlElicitationRequiredErrorTool } from "./trigger-url-elicitation-required-error.js";
+import { registerTriggerUrlElicitationTool } from "./trigger-url-elicitation.js";

 /**
 * Register the tools with the MCP server.
@@ -46,8 +45,7 @@ export const registerTools = (server: McpServer) => {
 export const registerConditionalTools = (server: McpServer) => {
  registerGetRootsListTool(server);
  registerTriggerElicitationRequestTool(server);
-  registerTriggerUrlElicitationRequestTool(server);
-  registerTriggerUrlElicitationRequiredErrorTool(server);
+  registerTriggerUrlElicitationTool(server);
  registerTriggerSamplingRequestTool(server);
  // Task-based research tool (uses experimental tasks API)
  registerSimulateResearchQueryTool(server);
--- a/src/everything/tools/trigger-url-elicitation-required-error.ts
+++ b/src/everything/tools/trigger-url-elicitation-required-error.ts
@@ -1,79 +0,0 @@
-import { randomUUID } from "node:crypto";
-import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
-import {
-  CallToolResult,
-  ElicitRequestURLParams,
-  UrlElicitationRequiredError,
-} from "@modelcontextprotocol/sdk/types.js";
-import { z } from "zod";
-
-// Tool input schema
-const TriggerUrlElicitationRequiredErrorSchema = z.object({
-  url: z.string().url().describe("The URL the user should open"),
-  message: z
-    .string()
-    .default("This request requires more information.")
-    .describe("Message shown to the user for the URL elicitation"),
-  elicitationId: z
-    .string()
-    .optional()
-    .describe("Optional explicit elicitation ID. Defaults to a random UUID."),
-});
-
-// Tool configuration
-const name = "trigger-url-elicitation-required-error";
-const config = {
-  title: "Trigger URL Elicitation Required Error Tool",
-  description:
-    "Returns MCP error -32042 (URL elicitation required) so clients can handle URL-mode elicitations via the error path.",
-  inputSchema: TriggerUrlElicitationRequiredErrorSchema,
-};
-
-/**
- * Registers the 'trigger-url-elicitation-required-error' tool.
- *
- * This tool demonstrates the MCP error path for URL elicitation by throwing
- * UrlElicitationRequiredError (code -32042) from a tool handler.
- *
- * @param {McpServer} server - The McpServer instance where the tool will be registered.
- */
-export const registerTriggerUrlElicitationRequiredErrorTool = (
-  server: McpServer
-) => {
-  const clientCapabilities = server.server.getClientCapabilities() || {};
-  const clientElicitationCapabilities = clientCapabilities.elicitation as
-    | {
-        url?: object;
-      }
-    | undefined;
-
-  const clientSupportsUrlElicitation =
-    clientElicitationCapabilities?.url !== undefined;
-
-  if (clientSupportsUrlElicitation) {
-    server.registerTool(
-      name,
-      config,
-      async (args): Promise<CallToolResult> => {
-        const validatedArgs = TriggerUrlElicitationRequiredErrorSchema.parse(args);
-        const { url, message, elicitationId: requestedElicitationId } =
-          validatedArgs;
-
-        const elicitationId = requestedElicitationId ?? randomUUID();
-
-        const requiredElicitation: ElicitRequestURLParams = {
-          mode: "url",
-          url,
-          message,
-          elicitationId,
-        };
-
-        throw new UrlElicitationRequiredError(
-          [requiredElicitation],
-          "This request requires more information."
-        );
-      }
-    );
-  }
-};
-
--- a/src/everything/tools/trigger-url-elicitation-request.ts
+++ b/src/everything/tools/trigger-url-elicitation-request.ts
@@ -4,11 +4,12 @@ import {
  CallToolResult,
  ElicitRequestURLParams,
  ElicitResultSchema,
+  UrlElicitationRequiredError,
 } from "@modelcontextprotocol/sdk/types.js";
 import { z } from "zod";

 // Tool input schema
-const TriggerUrlElicitationRequestSchema = z.object({
+const TriggerUrlElicitationSchema = z.object({
  url: z.string().url().describe("The URL the user should open"),
  message: z
    .string()
@@ -18,32 +19,43 @@ const TriggerUrlElicitationRequestSchema = z.object({
    .string()
    .optional()
    .describe("Optional explicit elicitation ID. Defaults to a random UUID."),
-  sendCompletionNotification: z
+  errorPath: z
    .boolean()
    .default(false)
    .describe(
-      "If true, sends notifications/elicitation/complete after an accepted URL elicitation."
+      "Controls which elicitation mechanism is used. " +
+        "When false (default), sends an elicitation/create request (request path). " +
+        "When true, throws a UrlElicitationRequiredError (MCP error code -32042) so the client handles " +
+        "the URL elicitation via the error path rather than waiting for a response."
    ),
 });

 // Tool configuration
-const name = "trigger-url-elicitation-request";
+const name = "trigger-url-elicitation";
 const config = {
-  title: "Trigger URL Elicitation Request Tool",
+  title: "Trigger URL Elicitation Tool",
  description:
-    "Trigger an out-of-band URL elicitation request so the client can direct the user to a browser flow.",
-  inputSchema: TriggerUrlElicitationRequestSchema,
+    "Trigger a URL elicitation so the client can direct the user to a browser flow. " +
+    "Supports two mechanisms: the request path (elicitation/create, default) which awaits the user's " +
+    "response, and the error path (UrlElicitationRequiredError, -32042) which signals the client " +
+    "to handle URL elicitation via the error response. Set errorPath=true to use the error path.",
+  inputSchema: TriggerUrlElicitationSchema,
 };

 /**
- * Registers the 'trigger-url-elicitation-request' tool.
+ * Registers the 'trigger-url-elicitation' tool.
 *
 * This tool only registers when the client advertises URL-mode elicitation
 * capability (clientCapabilities.elicitation.url).
 *
+ * Depending on the `errorPath` argument it either:
+ *  - Sends an `elicitation/create` request and awaits the result (request path), or
+ *  - Throws a `UrlElicitationRequiredError` (MCP error -32042) for the client to
+ *    handle via the error path.
+ *
 * @param {McpServer} server - The McpServer instance where the tool will be registered.
 */
-export const registerTriggerUrlElicitationRequestTool = (server: McpServer) => {
+export const registerTriggerUrlElicitationTool = (server: McpServer) => {
  const clientCapabilities = server.server.getClientCapabilities() || {};
  const clientElicitationCapabilities = clientCapabilities.elicitation as
    | {
@@ -59,27 +71,36 @@ export const registerTriggerUrlElicitationRequestTool = (server: McpServer) => {
      name,
      config,
      async (args, extra): Promise<CallToolResult> => {
-        const validatedArgs = TriggerUrlElicitationRequestSchema.parse(args);
+        const validatedArgs = TriggerUrlElicitationSchema.parse(args);
        const {
          url,
          message,
          elicitationId: requestedElicitationId,
-          sendCompletionNotification,
+          errorPath,
        } = validatedArgs;

        const elicitationId = requestedElicitationId ?? randomUUID();

-        const params: ElicitRequestURLParams = {
+        const elicitationParams: ElicitRequestURLParams = {
          mode: "url",
-          message,
          url,
+          message,
          elicitationId,
        };

+        // Error path: throw UrlElicitationRequiredError (-32042) for the client to handle
+        if (errorPath) {
+          throw new UrlElicitationRequiredError(
+            [elicitationParams],
+            "This request requires browser-based authorization."
+          );
+        }
+
+        // Request path: send elicitation/create and await the user's response
        const elicitationResult = await extra.sendRequest(
          {
            method: "elicitation/create",
-            params,
+            params: elicitationParams,
          },
          ElicitResultSchema,
          { timeout: 10 * 60 * 1000 /* 10 minutes */ }
@@ -95,19 +116,6 @@ export const registerTriggerUrlElicitationRequestTool = (server: McpServer) => {
          },
        ];

-        if (
-          sendCompletionNotification &&
-          elicitationResult.action === "accept"
-        ) {
-          const notifyElicitationComplete =
-            server.server.createElicitationCompletionNotifier(elicitationId);
-          await notifyElicitationComplete();
-          content.push({
-            type: "text",
-            text: `Sent notifications/elicitation/complete for ${elicitationId}.`,
-          });
-        }
-
        content.push({
          type: "text",
          text: `Raw result: ${JSON.stringify(elicitationResult, null, 2)}`,
@@ -118,4 +126,3 @@ export const registerTriggerUrlElicitationRequestTool = (server: McpServer) => {
    );
  }
 };
-