From 23456ce7dd12ee8e26677476e4563e3b13c492d5 Mon Sep 17 00:00:00 2001
From: Niels Kaspers <kaspersniels@gmail.com>
Date: Thu, 12 Mar 2026 09:07:55 +0200
Subject: [PATCH] feat(sequential-thinking): add tool annotations

Add readOnlyHint, destructiveHint, idempotentHint, and openWorldHint
annotations to the sequentialthinking tool, consistent with how
server-filesystem annotates its tools.

The tool is pure computation (readOnly), produces deterministic
structure for the same input (idempotent), and makes no external
calls (not openWorld).

Fixes #3403
---
 src/sequentialthinking/index.ts | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/sequentialthinking/index.ts b/src/sequentialthinking/index.ts
index 809086a94c..a3c34ccadb 100644
--- a/src/sequentialthinking/index.ts
+++ b/src/sequentialthinking/index.ts
@@ -81,6 +81,12 @@ You should:
       branchId: z.string().optional().describe("Branch identifier"),
       needsMoreThoughts: z.boolean().optional().describe("If more thoughts are needed")
     },
+    annotations: {
+      readOnlyHint: true,
+      destructiveHint: false,
+      idempotentHint: true,
+      openWorldHint: false,
+    },
     outputSchema: {
       thoughtNumber: z.number(),
       totalThoughts: z.number(),