fix(web): send a cancellation notification when cancelling an ordinary tool call (#1458) (#1463)

* fix(web): send a cancellation notification when cancelling an ordinary tool call (#1458)

The Tool detail panel's Cancel button was a silent no-op for ordinary
(non-task) tool calls: App.onCancelToolCall found no captured taskId and
did nothing, leaving the button looking actionable while the call ran on.

Wire request cancellation through the MCP cancellation flow. callTool now
tracks the in-flight call with an AbortController whose signal is threaded
into the SDK request options; aborting it makes the SDK send a
notifications/cancelled for that request and reject the pending call.
cancelToolCall() performs the abort. callTool surfaces the cancellation as
a ToolCallCancelledError (without recording a failed call), which App
clears as a clean cancel plus a short confirmation toast.

Task-augmented calls are unchanged: they have a server-side task and are
still cancelled via cancelRequestorTask (#1457).

Closes #1458

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix(web): address review — distinguish disconnect from cancel; tidy callTool params

Review follow-ups on #1463:

- Disconnect no longer surfaces as "Tool call cancelled". The catch in
  callToolWithRetries now throws ToolCallCancelledError only when the abort
  reason matches the deliberate user-cancel reason (TOOL_CALL_CANCELLED_REASON);
  a disconnect aborts the same controller with a different reason and falls
  through to the normal error path, so no misleading toast.
- Note the activeToolCallAbortController slot is shared (last-writer-wins)
  across all callTool callers.
- Fold callToolWithRetries/attemptToolCall's long positional parameter list into
  a single ToolCallRequest object; move the URL-elicitation loop state into
  callToolWithRetries.

Adds an integration test that a disconnect mid-call rejects as an ordinary
error (not ToolCallCancelledError), using a slow send_progress call over HTTP.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/web/src/test/integration/mcp/inspectorClient.test.ts

@@ -13,6 +13,7 @@ import {
   ManagedToolsState,
 } from "@inspector/core/mcp/state/index.js";
 import { createTransportNode } from "@inspector/core/mcp/node/transport.js";
+import { ToolCallCancelledError } from "@inspector/core/mcp/toolCallCancelledError.js";
 import { SamplingCreateMessage } from "@inspector/core/mcp/samplingCreateMessage.js";
 import { ElicitationCreateMessage } from "@inspector/core/mcp/elicitationCreateMessage.js";
 import {
@@ -29,6 +30,7 @@ import {
   createCollectUrlElicitationTool,
   createUrlElicitationFormTool,
   createSendNotificationTool,
+  createSendProgressTool,
   createListRootsTool,
   createArgsPrompt,
   createNumberedTools,
@@ -950,6 +952,89 @@ describe("InspectorClient", () => {
       }
     });
 
+    it("cancelToolCall() is a no-op (returns false) when no call is in flight", () => {
+      expect(client!.cancelToolCall()).toBe(false);
+    });
+
+    it("ToolCallCancelledError carries the tool name when known, and reads generically without one", () => {
+      expect(new ToolCallCancelledError("echo").message).toContain('"echo"');
+      expect(new ToolCallCancelledError().message).toBe(
+        "Tool call was cancelled.",
+      );
+    });
+
+    it("cancelToolCall() aborts the in-flight call: sends notifications/cancelled, rejects with ToolCallCancelledError, and records no failed call", async () => {
+      const tool = await getTool(client!, "echo");
+
+      const messages: MessageEntry[] = [];
+      client!.addEventListener("message", (event) => {
+        messages.push(event.detail);
+      });
+      let failedCallCount = 0;
+      client!.addEventListener("toolCallResultChange", (event) => {
+        if (!event.detail.success) failedCallCount++;
+      });
+
+      // Start the call, then cancel synchronously — before the response can be
+      // processed — so the abort always wins the race regardless of tool speed.
+      const promise = client!.callTool(tool, { message: "hello world" });
+      expect(client!.cancelToolCall()).toBe(true);
+
+      await expect(promise).rejects.toBeInstanceOf(ToolCallCancelledError);
+
+      // The MCP cancellation flow: a notifications/cancelled reaches the server.
+      const cancelled = messages.find(
+        (m) =>
+          m.direction === "notification" &&
+          "method" in m.message &&
+          m.message.method === "notifications/cancelled",
+      );
+      expect(cancelled).toBeDefined();
+
+      // Cancelling is intentional, so it is not recorded as a failed tool call.
+      expect(failedCallCount).toBe(0);
+
+      // The controller was cleared, so a second cancel is a no-op.
+      expect(client!.cancelToolCall()).toBe(false);
+    });
+
+    it("a disconnect mid-call does not surface as a ToolCallCancelledError", async () => {
+      // disconnect() aborts the same in-flight controller, but with a different
+      // reason than cancelToolCall(). The call must reject as an ordinary error,
+      // not a user-cancel — so App doesn't show a misleading "cancelled" toast.
+      // Use a genuinely slow tool (over HTTP) so the call is still in flight when
+      // we disconnect; echo would complete before teardown.
+      await client!.disconnect();
+      server = createTestServerHttp({
+        serverInfo: createTestServerInfo(),
+        tools: [createSendProgressTool()],
+      });
+      await server.start();
+      client = new InspectorClient(
+        { type: "streamable-http", url: server.url },
+        {
+          environment: { transport: createTransportNode },
+          clientIdentity: { name: "test", version: "1.0.0" },
+        },
+      );
+      await client.connect();
+      const tool = await getTool(client, "send_progress");
+
+      // 20 units * 200ms ≈ 4s — comfortably still running when we disconnect.
+      const promise = client.callTool(tool, { units: 20, delayMs: 200 });
+      await new Promise((resolve) => setTimeout(resolve, 150));
+      await client.disconnect();
+
+      let caught: unknown;
+      try {
+        await promise;
+      } catch (err) {
+        caught = err;
+      }
+      expect(caught).toBeDefined();
+      expect(caught).not.toBeInstanceOf(ToolCallCancelledError);
+    });
+
     it("should paginate tools when maxPageSize is set", async () => {
       // Disconnect and create a new server with pagination
       await client!.disconnect();