From 04f1e767b2644667f5831d60737d0c025521057a Mon Sep 17 00:00:00 2001
From: Josh Phillips <1442552485+j1philli@users.noreply.github.com>
Date: Tue, 13 Jan 2026 22:55:57 +0000
Subject: [PATCH] Fix OpenAI tool_call id length for OpenRouter

---
 src/agents/tool-call-id.ts | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/agents/tool-call-id.ts b/src/agents/tool-call-id.ts
index a3bfab131..c4aec7e5b 100644
--- a/src/agents/tool-call-id.ts
+++ b/src/agents/tool-call-id.ts
@@ -24,21 +24,25 @@ function shortHash(text: string): string {
 }
 
 function makeUniqueToolId(params: { id: string; used: Set<string> }): string {
-  const base = sanitizeToolCallId(params.id);
+  const MAX_LEN = 40;
+
+  const base = sanitizeToolCallId(params.id).slice(0, MAX_LEN);
   if (!params.used.has(base)) return base;
 
   const hash = shortHash(params.id);
-  const maxBaseLen = 64 - 1 - hash.length;
+  const maxBaseLen = MAX_LEN - 1 - hash.length;
   const clippedBase = base.length > maxBaseLen ? base.slice(0, maxBaseLen) : base;
   const candidate = `${clippedBase}_${hash}`;
   if (!params.used.has(candidate)) return candidate;
 
   for (let i = 2; i < 1000; i += 1) {
-    const next = `${candidate}_${i}`;
+    const suffix = `_${i}`;
+    const next = `${candidate.slice(0, MAX_LEN - suffix.length)}${suffix}`;
     if (!params.used.has(next)) return next;
   }
 
-  return `${candidate}_${Date.now()}`;
+  const ts = `_${Date.now()}`;
+  return `${candidate.slice(0, MAX_LEN - ts.length)}${ts}`;
 }
 
 function rewriteAssistantToolCallIds(params: {