diff --git a/apps/mcp-server/src/tools/hivemind.test.ts b/apps/mcp-server/src/tools/hivemind.test.ts
new file mode 100644
index 0000000..eab583b
--- /dev/null
+++ b/apps/mcp-server/src/tools/hivemind.test.ts
@@ -0,0 +1,83 @@
+import { mkdirSync, mkdtempSync, rmSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { performance } from 'node:perf_hooks';
+import { defaultSettings } from '@colony/config';
+import { MemoryStore } from '@colony/core';
+import { Client } from '@modelcontextprotocol/sdk/client';
+import { InMemoryTransport } from '@modelcontextprotocol/sdk/inMemory.js';
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import { buildServer } from '../server.js';
+
+let dir: string;
+let store: MemoryStore;
+let client: Client;
+
+beforeEach(async () => {
+  dir = mkdtempSync(join(tmpdir(), 'colony-hivemind-'));
+  store = new MemoryStore({ dbPath: join(dir, 'data.db'), settings: defaultSettings });
+  const server = buildServer(store, defaultSettings);
+  const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+  client = new Client({ name: 'test', version: '0.0.0' });
+  await Promise.all([server.connect(serverTransport), client.connect(clientTransport)]);
+});
+
+afterEach(async () => {
+  await client.close();
+  store.close();
+  rmSync(dir, { recursive: true, force: true });
+});
+
+describe('hivemind_context performance', () => {
+  it('keeps the compact startup path bounded with large telemetry history', async () => {
+    const repoRoot = join(dir, 'repo');
+    mkdirSync(repoRoot, { recursive: true });
+    store.startSession({ id: 'history', ide: 'test', cwd: repoRoot });
+
+    for (let i = 0; i < 2000; i += 1) {
+      const tool = i % 10 === 0 ? 'Edit' : 'mcp__colony__task_list';
+      store.addObservation({
+        session_id: 'history',
+        kind: 'tool_use',
+        content: tool,
+        metadata: {
+          tool,
+          ...(tool === 'Edit' ? { file_path: `src/file-${i}.ts` } : {}),
+        },
+      });
+    }
+
+    for (let i = 0; i < 500; i += 1) {
+      store.addObservation({
+        session_id: 'history',
+        kind: 'note',
+        content: `background observation ${i}`,
+      });
+    }
+
+    const start = performance.now();
+    const res = await client.callTool({
+      name: 'hivemind_context',
+      arguments: {
+        repo_root: repoRoot,
+        session_id: 'agent-session',
+        agent: 'codex',
+        limit: 5,
+      },
+    });
+    const elapsedMs = performance.now() - start;
+    const text = (res.content as Array<{ type: string; text: string }>)[0]?.text ?? '{}';
+    const payload = JSON.parse(text) as {
+      summary: {
+        adoption_nudges: unknown[];
+        memory_hit_count: number;
+        ready_work_count: number;
+      };
+    };
+
+    expect(elapsedMs).toBeLessThan(500);
+    expect(payload.summary.memory_hit_count).toBe(0);
+    expect(payload.summary.adoption_nudges).toEqual([]);
+    expect(payload.summary.ready_work_count).toBe(0);
+  });
+});
diff --git a/apps/mcp-server/src/tools/hivemind.ts b/apps/mcp-server/src/tools/hivemind.ts
index ae42224..a918117 100644
--- a/apps/mcp-server/src/tools/hivemind.ts
+++ b/apps/mcp-server/src/tools/hivemind.ts
@@ -118,6 +118,7 @@ export function register(server: McpServer, ctx: ToolContext): void {
               files: files ?? [],
             })
           : null;
+        const explicitQuery = query?.trim() ?? '';
         const contextQuery = localMode
           ? buildLocalContextQuery({
               query,
@@ -129,7 +130,7 @@ export function register(server: McpServer, ctx: ToolContext): void {
         let memoryHits: SearchResult[] = [];
         let negativeWarnings: CompactNegativeWarning[] = [];
 
-        if (contextQuery) {
+        if (shouldSearchContext({ explicitQuery, localMode }) && contextQuery) {
           const e = (await resolveEmbedder()) ?? undefined;
           memoryHits = localMode
             ? await searchLocalMemoryHits(
@@ -229,7 +230,9 @@ export function register(server: McpServer, ctx: ToolContext): void {
             })
           : undefined;
         const readyWorkCount = countReadyWork(store, { repo_root, repo_roots });
-        const adoptionNudges = buildAdoptionNudges(store);
+        const adoptionNudges = shouldBuildAdoptionNudges({ explicitQuery, localMode })
+          ? buildAdoptionNudges(store)
+          : [];
         const mustCheckAttention = !hasRecentAttentionInboxCall(
           store,
           attentionIdentity.session_id,
@@ -280,6 +283,13 @@ function countReadyWork(
   store: MemoryStore,
   input: { repo_root: string | undefined; repo_roots: string[] | undefined },
 ): number {
+  if (input.repo_root !== undefined && (input.repo_roots?.length ?? 0) === 0) {
+    return listPlans(store, { repo_root: input.repo_root, limit: 2000 }).reduce(
+      (total, plan) => total + plan.next_available.length,
+      0,
+    );
+  }
+
   const roots = new Set(
     [input.repo_root, ...(input.repo_roots ?? [])]
       .filter((root): root is string => typeof root === 'string' && root.trim().length > 0)
@@ -290,6 +300,17 @@ function countReadyWork(
     .reduce((total, plan) => total + plan.next_available.length, 0);
 }
 
+function shouldSearchContext(input: { explicitQuery: string; localMode: boolean }): boolean {
+  return input.localMode || input.explicitQuery.length > 0;
+}
+
+function shouldBuildAdoptionNudges(input: {
+  explicitQuery: string;
+  localMode: boolean;
+}): boolean {
+  return input.localMode || input.explicitQuery.length > 0;
+}
+
 function buildAdoptionNudges(store: MemoryStore, now = Date.now()): HivemindAdoptionNudge[] {
   try {
     return adoptionNudgesFromMetrics(store, now);