fix(tools): stop cancelled calls before execution and discard late results

src/tools/catalog-cancellation.test.mjs

@@ -0,0 +1,41 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { composeCatalog, defineTool } from './catalog.js';
+test('cancelled catalog calls cannot execute or return late results', async () => {
+  let calls = 0,
+    release,
+    block = false;
+  const action = defineTool({
+    name: 'fixture_action',
+    kind: 'action',
+    title: 'Fixture',
+    description: 'Offline fixture',
+    inputSchema: { type: 'object' },
+    run: async () => {
+      calls++;
+      return block
+        ? new Promise((r) => (release = r))
+        : { summary: 'fixture', data: {} };
+    },
+  });
+  const catalog = composeCatalog({ tools: [action] });
+  const c = new AbortController();
+  c.abort();
+  await assert.rejects(
+    catalog.call('fixture_action', {}, { signal: c.signal }),
+    { name: 'AbortError' },
+  );
+  assert.equal(calls, 0);
+  block = true;
+  const running = new AbortController();
+  const pending = catalog.call(
+    'fixture_action',
+    {},
+    { signal: running.signal },
+  );
+  while (!release) await Promise.resolve();
+  running.abort();
+  release({ summary: 'late', data: {} });
+  await assert.rejects(pending, { name: 'AbortError' });
+  assert.equal(calls, 1);
+});

src/tools/catalog.js

@@ -178,6 +178,7 @@ export function composeCatalog({
     return chain({ tool, args, signal, ...(parent ? { parent } : {}) });
   };
   const execute = async ({ tool, args, signal }) => {
+    signal?.throwIfAborted();
     const problems = validateValue(tool.inputSchema, args);
     if (problems.length)
       throw new ToolError('invalid_arguments', problems.join('; '));
@@ -194,6 +195,7 @@ export function composeCatalog({
     } catch (error) {
       throw fromSourceError(error);
     }
+    signal?.throwIfAborted();
     if (!result || typeof result.summary !== 'string' || !result.data)
       throw new TypeError(`${tool.name} returned no summary or data`);
     if (