fix: make MCP task recall tolerate search backend outages

Author: ZengLiangYi

server/src/services/memory/recall.test.ts

@@ -133,6 +133,51 @@ test('recallForTask returns no-matches when semantic hits are fully filtered out
   assert.deepEqual(result.global_memories, []);
 });
 
+test('recallForTask returns an empty recall with warning when semantic search backend is unavailable', async () => {
+  const db = {
+    exec(sql: string) {
+      if (sql.includes('SELECT canonical_key FROM project_key_aliases')) {
+        return [{ columns: ['canonical_key'], values: [] }];
+      }
+      if (sql.includes('FROM project_key_aliases')) {
+        return [{
+          columns: ['alias_key'],
+          values: [['git:project-a']],
+        }];
+      }
+      throw new Error(`Unexpected SQL: ${sql}`);
+    },
+  };
+
+  const result = await recallForTask(
+    {
+      mode: 'task',
+      task: {
+        goal: 'Evaluate Glama MCP listing quality',
+        task_kind: 'config',
+        project_key: 'git:project-a',
+      },
+      options: {
+        project_limit: 3,
+        global_limit: 0,
+        include_relations: false,
+      },
+    },
+    {
+      db: db as never,
+      semanticSearch: async () => {
+        throw new Error('Cannot connect to API: connect ECONNREFUSED 127.0.0.1:11434');
+      },
+    },
+  );
+
+  assert.equal(result.reason, 'no-matches');
+  assert.deepEqual(result.project_memories, []);
+  assert.deepEqual(result.global_memories, []);
+  assert.match(result.warnings.join('\n'), /Semantic memory recall unavailable/);
+  assert.match(result.warnings.join('\n'), /ECONNREFUSED/);
+});
+
 test('recallForTask derives project_key from project_dir when the caller does not provide one', async () => {
   const projectDir = process.cwd().replace(/\\/g, '/');
   const derivedProjectKey = deriveProjectKey(

server/src/services/memory/recall.ts

@@ -68,13 +68,27 @@ export async function recallForTask(
     );
   }
 
-  const hits = await search(
-    [request.task.goal, ...(request.task.error_signatures ?? [])]
-      .filter(Boolean)
-      .join('\n'),
-    Math.max((projectLimit + globalLimit) * 3, 1),
-    includeRelations,
-  );
+  let hits: Awaited<ReturnType<typeof semanticSearch>>;
+  try {
+    hits = await search(
+      [request.task.goal, ...(request.task.error_signatures ?? [])]
+        .filter(Boolean)
+        .join('\n'),
+      Math.max((projectLimit + globalLimit) * 3, 1),
+      includeRelations,
+    );
+  } catch (error) {
+    const message = error instanceof Error ? error.message : String(error);
+    warnings.push(`Semantic memory recall unavailable: ${message}`);
+    return {
+      mode: request.mode,
+      project_key: canonicalProjectKey,
+      reason: canonicalProjectKey ? 'no-matches' : 'no-project-key',
+      warnings,
+      project_memories: [],
+      global_memories: [],
+    };
+  }
   const noteIds = [...new Set(hits.map((hit) => hit.noteId))];
 
   if (noteIds.length === 0) {