From 6bcde3763c1a802c62cb1b157f1ced2e2cd5064c Mon Sep 17 00:00:00 2001
From: somuai <jobsoumyajit6124@gmail.com>
Date: Fri, 4 Sep 2026 01:39:06 +0530
Subject: [PATCH] fix(sequentialthinking): set accurate readOnlyHint and
 idempotentHint annotations

- Set readOnlyHint: false because the server maintains per-session thoughtHistory and branches state
- Set idempotentHint: false because sequential calls produce different history lengths
- Add regression assertion in input-schema.test.ts
- Fixes #4721
---
 .../__tests__/input-schema.test.ts                   | 12 ++++++++++++
 src/sequentialthinking/index.ts                      |  4 ++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/sequentialthinking/__tests__/input-schema.test.ts b/src/sequentialthinking/__tests__/input-schema.test.ts
index 4ff7be663c..6bcc354f08 100644
--- a/src/sequentialthinking/__tests__/input-schema.test.ts
+++ b/src/sequentialthinking/__tests__/input-schema.test.ts
@@ -30,6 +30,18 @@ describe.skipIf(!existsSync(distIndexPath))('sequentialthinking input schema', (
     await client?.close();
   });
 
+  it('advertises accurate annotations (stateful and non-idempotent)', async () => {
+    const { tools } = await client.listTools();
+    const tool = tools.find(t => t.name === 'sequentialthinking');
+    expect(tool).toBeDefined();
+    expect(tool!.annotations).toEqual({
+      readOnlyHint: false,
+      destructiveHint: false,
+      idempotentHint: false,
+      openWorldHint: false,
+    });
+  });
+
   it('advertises nextThoughtNeeded as required', async () => {
     const { tools } = await client.listTools();
     const tool = tools.find(t => t.name === 'sequentialthinking');
diff --git a/src/sequentialthinking/index.ts b/src/sequentialthinking/index.ts
index 1ae09d1db8..8be1f9a568 100644
--- a/src/sequentialthinking/index.ts
+++ b/src/sequentialthinking/index.ts
@@ -93,9 +93,9 @@ You should:
       needsMoreThoughts: coercedBoolean.optional().describe("If more thoughts are needed")
     },
     annotations: {
-      readOnlyHint: true,
+      readOnlyHint: false,
       destructiveHint: false,
-      idempotentHint: true,
+      idempotentHint: false,
       openWorldHint: false,
     },
     outputSchema: {