From eb5cc873eaba045a19bdb2589b8ea3b4d2c40765 Mon Sep 17 00:00:00 2001
From: YeonGyu-Kim <code.yeon.gyu@gmail.com>
Date: Sat, 7 Feb 2026 13:12:47 +0900
Subject: [PATCH] fix: trim whitespace from tool names to prevent invalid tool
 calls

Some models (e.g. kimi-k2.5) return tool names with leading spaces
like ' delegate_task', causing tool matching to fail.

Add .trim() in transformToolName() and defensive trim in claude-code-hooks.

Fixes #1568
---
 src/hooks/claude-code-hooks/index.ts |   2 +-
 src/shared/tool-name.test.ts         | 155 +++++++++++++++++++++++++++
 src/shared/tool-name.ts              |   9 +-
 3 files changed, 161 insertions(+), 5 deletions(-)
 create mode 100644 src/shared/tool-name.test.ts

diff --git a/src/hooks/claude-code-hooks/index.ts b/src/hooks/claude-code-hooks/index.ts
index f4b2b1149..9555ea797 100644
--- a/src/hooks/claude-code-hooks/index.ts
+++ b/src/hooks/claude-code-hooks/index.ts
@@ -175,7 +175,7 @@ export function createClaudeCodeHooksHook(
       input: { tool: string; sessionID: string; callID: string },
       output: { args: Record<string, unknown> }
     ): Promise<void> => {
-      if (input.tool === "todowrite" && typeof output.args.todos === "string") {
+      if (input.tool.trim() === "todowrite" && typeof output.args.todos === "string") {
         let parsed: unknown
         try {
           parsed = JSON.parse(output.args.todos)
diff --git a/src/shared/tool-name.test.ts b/src/shared/tool-name.test.ts
new file mode 100644
index 000000000..3cafe75ab
--- /dev/null
+++ b/src/shared/tool-name.test.ts
@@ -0,0 +1,155 @@
+import { describe, it, expect } from "bun:test"
+import { transformToolName } from "./tool-name"
+
+describe("transformToolName", () => {
+  describe("whitespace trimming", () => {
+    it("trims leading whitespace from tool name", () => {
+      // given
+      const toolName = " delegate_task"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("DelegateTask")
+    })
+
+    it("trims trailing whitespace from tool name", () => {
+      // given
+      const toolName = "delegate_task "
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("DelegateTask")
+    })
+
+    it("trims both leading and trailing whitespace", () => {
+      // given
+      const toolName = " delegate_task "
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("DelegateTask")
+    })
+
+    it("applies special mapping after trimming whitespace", () => {
+      // given
+      const toolName = " webfetch"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("WebFetch")
+    })
+
+    it("handles simple case with leading and trailing spaces", () => {
+      // given
+      const toolName = " read "
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("Read")
+    })
+  })
+
+  describe("special tool mappings", () => {
+    it("maps webfetch to WebFetch", () => {
+      // given
+      const toolName = "webfetch"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("WebFetch")
+    })
+
+    it("maps websearch to WebSearch", () => {
+      // given
+      const toolName = "websearch"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("WebSearch")
+    })
+
+    it("maps todoread to TodoRead", () => {
+      // given
+      const toolName = "todoread"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("TodoRead")
+    })
+
+    it("maps todowrite to TodoWrite", () => {
+      // given
+      const toolName = "todowrite"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("TodoWrite")
+    })
+  })
+
+  describe("kebab-case and snake_case conversion", () => {
+    it("converts snake_case to PascalCase", () => {
+      // given
+      const toolName = "delegate_task"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("DelegateTask")
+    })
+
+    it("converts kebab-case to PascalCase", () => {
+      // given
+      const toolName = "call-omo-agent"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("CallOmoAgent")
+    })
+  })
+
+  describe("simple capitalization", () => {
+    it("capitalizes simple single-word tool names", () => {
+      // given
+      const toolName = "read"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("Read")
+    })
+
+    it("preserves capitalization of already capitalized names", () => {
+      // given
+      const toolName = "Write"
+
+      // when
+      const result = transformToolName(toolName)
+
+      // then
+      expect(result).toBe("Write")
+    })
+  })
+})
diff --git a/src/shared/tool-name.ts b/src/shared/tool-name.ts
index d94ede6dc..b93b07021 100644
--- a/src/shared/tool-name.ts
+++ b/src/shared/tool-name.ts
@@ -13,14 +13,15 @@ function toPascalCase(str: string): string {
 }
 
 export function transformToolName(toolName: string): string {
-  const lower = toolName.toLowerCase()
+  const trimmed = toolName.trim()
+  const lower = trimmed.toLowerCase()
   if (lower in SPECIAL_TOOL_MAPPINGS) {
     return SPECIAL_TOOL_MAPPINGS[lower]
   }
 
-  if (toolName.includes("-") || toolName.includes("_")) {
-    return toPascalCase(toolName)
+  if (trimmed.includes("-") || trimmed.includes("_")) {
+    return toPascalCase(trimmed)
   }
 
-  return toolName.charAt(0).toUpperCase() + toolName.slice(1)
+  return trimmed.charAt(0).toUpperCase() + trimmed.slice(1)
 }