# v0.4.30 (2026-05-11)

## Features
- MCP stdio→SSE bridge: expose local stdio MCP plugins over SSE (api/mcp/[plugin]/sse, /message)
- Dynamic Linux cert resolution + NSS DB injection (Debian/Arch/Fedora/openSUSE, Chrome/Chromium/Firefox incl. snap) (#1010)
- Cowork tool: expanded settings UI & API
- GitBook docs (DocsContent, DocsLayout)
## Fixes
- OAuth callback postMessage scoped to expected origins (CWE-1385) (#998)
- Re-enable TLS verification on DNS-bypass fetch (CWE-295) (#998)
- Normalize `developer` role → `system` for OpenAI-format providers (Deepseek, Groq, …) (#1011, closes #773)
- Respect `PORT` env in internal model-test fetch (#1014)
- Dropdown text readability in dark theme on usage page (#997)
## Improvements
- Refactor Claude CLI spoof headers into shared constant
- Tool deduper utility in open-sse handlers

open-sse/handlers/chatCore.js

@@ -16,6 +16,7 @@ import { handleForcedSSEToJson } from "./chatCore/sseToJsonHandler.js";
 import { handleNonStreamingResponse } from "./chatCore/nonStreamingHandler.js";
 import { handleStreamingResponse, buildOnStreamComplete } from "./chatCore/streamingHandler.js";
 import { detectClientTool, isNativePassthrough } from "../utils/clientDetector.js";
+import { dedupeTools } from "../utils/toolDeduper.js";
 import { injectCaveman } from "../rtk/caveman.js";
 import { compressMessages, formatRtkLog } from "../rtk/index.js";
 
@@ -94,6 +95,15 @@ export async function handleChatCore({ body, modelInfo, credentials, log, onCred
     translatedBody.model = model;
   }
 
+  // Dedupe duplicate built-in tools when equivalent MCP tools are present (Claude clients only).
+  if (clientTool === "claude" && Array.isArray(translatedBody.tools)) {
+    const { tools: deduped, stripped } = dedupeTools(translatedBody.tools);
+    if (stripped.length > 0) {
+      translatedBody.tools = deduped;
+      log?.debug?.("TOOLDEDUP", `stripped ${stripped.length}: ${stripped.slice(0, 3).join(", ")}${stripped.length > 3 ? "..." : ""}`);
+    }
+  }
+
   // Token savers: applied at the final body just before dispatch
   // Covers both passthrough (source shape) and translated (target shape) flows
   const finalFormat = passthrough ? sourceFormat : targetFormat;