diff --git a/cli/release/package.json b/cli/release/package.json
index 1f46a0c0f..b6d6c62fa 100644
--- a/cli/release/package.json
+++ b/cli/release/package.json
@@ -1,6 +1,6 @@
 {
   "name": "codebuff",
-  "version": "1.0.669",
+  "version": "1.0.671",
   "description": "AI coding agent",
   "license": "MIT",
   "bin": {
diff --git a/cli/src/components/tools/__tests__/apply-patch.test.tsx b/cli/src/components/tools/__tests__/apply-patch.test.tsx
index 75154bd96..6e177757f 100644
--- a/cli/src/components/tools/__tests__/apply-patch.test.tsx
+++ b/cli/src/components/tools/__tests__/apply-patch.test.tsx
@@ -47,7 +47,7 @@ describe('ApplyPatchComponent', () => {
     expect(markup).toContain('src/new-file.ts')
   })
 
-  test('renders update_file operation with diff content', () => {
+  test('renders update_file operation without diff content while diff rendering is disabled', () => {
     const toolBlock = createToolBlock({
       type: 'update_file',
       path: 'src/existing.ts',
@@ -62,8 +62,8 @@ describe('ApplyPatchComponent', () => {
     const markup = renderToStaticMarkup(result?.content as React.ReactElement)
     expect(markup).toContain('Edit')
     expect(markup).toContain('src/existing.ts')
-    expect(markup).toContain('-oldLine')
-    expect(markup).toContain('+newLine')
+    expect(markup).not.toContain('-oldLine')
+    expect(markup).not.toContain('+newLine')
   })
 
   test('renders delete_file operation', () => {
diff --git a/cli/src/components/tools/diff-viewer.tsx b/cli/src/components/tools/diff-viewer.tsx
index 72ee7361f..37d613a9a 100644
--- a/cli/src/components/tools/diff-viewer.tsx
+++ b/cli/src/components/tools/diff-viewer.tsx
@@ -6,6 +6,8 @@ interface DiffViewerProps {
   diffText: string
 }
 
+const RENDER_DIFFS = false
+
 const DIFF_LINE_COLORS = {
   dark: {
     added: '#7ACC35',
@@ -50,6 +52,11 @@ const lineColor = (
 
 export const DiffViewer = ({ diffText }: DiffViewerProps) => {
   const theme = useTheme()
+
+  if (!RENDER_DIFFS) {
+    return null
+  }
+
   const lines = diffText.trim().split('\n')
 
   return (
diff --git a/cli/src/utils/__tests__/message-block-helpers.test.ts b/cli/src/utils/__tests__/message-block-helpers.test.ts
index d813de400..304514aab 100644
--- a/cli/src/utils/__tests__/message-block-helpers.test.ts
+++ b/cli/src/utils/__tests__/message-block-helpers.test.ts
@@ -39,10 +39,6 @@ describe('getAgentBaseName', () => {
     expect(getAgentBaseName('file-picker')).toBe('file-picker')
   })
 
-  test('normalizes direct tool aliases to canonical agent names', () => {
-    expect(getAgentBaseName('code_reviewer_lite')).toBe('code-reviewer-lite')
-  })
-
   test('handles scoped name without version', () => {
     expect(getAgentBaseName('codebuff/file-picker')).toBe('file-picker')
   })
diff --git a/cli/src/utils/__tests__/sdk-event-handlers.test.ts b/cli/src/utils/__tests__/sdk-event-handlers.test.ts
index b86566b43..051a59689 100644
--- a/cli/src/utils/__tests__/sdk-event-handlers.test.ts
+++ b/cli/src/utils/__tests__/sdk-event-handlers.test.ts
@@ -212,89 +212,6 @@ describe('sdk-event-handlers', () => {
     expect(getStreamingAgents().has('tool-1-0')).toBe(false)
   })
 
-  test('matches underscore direct-tool aliases to hyphenated agent ids', () => {
-    const { ctx, getMessages, getStreamingAgents } = createTestContext()
-    const handleEvent = createEventHandler(ctx)
-    const handleChunk = createStreamChunkHandler(ctx)
-
-    handleEvent({
-      type: 'tool_call',
-      toolCallId: 'tool-1',
-      toolName: 'spawn_agents',
-      input: {
-        agents: [
-          {
-            agent_type: 'code_reviewer_lite',
-            prompt: 'Review this change',
-          },
-        ],
-      },
-      agentId: 'main-agent',
-      parentAgentId: undefined,
-    } as any)
-
-    handleEvent({
-      type: 'subagent_start',
-      agentId: 'agent-real',
-      agentType: 'code-reviewer-lite',
-      displayName: 'Code Reviewer Lite',
-      onlyChild: true,
-      parentAgentId: undefined,
-      params: undefined,
-      prompt: 'Review this change',
-    })
-
-    handleChunk({
-      type: 'subagent_chunk',
-      agentId: 'agent-real',
-      agentType: 'code-reviewer-lite',
-      chunk: 'streamed review',
-    })
-
-    handleEvent({
-      type: 'subagent_finish',
-      agentId: 'agent-real',
-      agentType: 'code-reviewer-lite',
-      displayName: 'Code Reviewer Lite',
-      onlyChild: true,
-      parentAgentId: undefined,
-      params: undefined,
-      prompt: 'Review this change',
-    })
-
-    handleEvent({
-      type: 'tool_result',
-      toolCallId: 'tool-1',
-      toolName: 'spawn_agents',
-      output: [
-        {
-          type: 'json',
-          value: [
-            {
-              agentName: 'code-reviewer-lite',
-              agentType: 'code-reviewer-lite',
-              value: 'streamed review',
-            },
-          ],
-        },
-      ],
-    } as any)
-
-    const blocks = getMessages()[0].blocks ?? []
-    expect(blocks).toHaveLength(1)
-    const agentBlock = blocks[0] as AgentContentBlock
-    expect(agentBlock.agentId).toBe('agent-real')
-    expect(agentBlock.agentName).toBe('code-reviewer-lite')
-    expect(agentBlock.agentType).toBe('code-reviewer-lite')
-    expect(agentBlock.status).toBe('complete')
-    expect(agentBlock.blocks).toHaveLength(1)
-    expect(agentBlock.blocks?.[0]).toMatchObject({
-      type: 'text',
-      content: 'streamed review',
-    })
-    expect(getStreamingAgents().size).toBe(0)
-  })
-
   test('handles spawn_agents tool results and clears streaming agents', () => {
     const { ctx, getMessages, getStreamingAgents } = createTestContext()
     ctx.message.updater.addBlock(
diff --git a/cli/src/utils/__tests__/send-message-helpers.test.ts b/cli/src/utils/__tests__/send-message-helpers.test.ts
index 00f95b899..4967498cf 100644
--- a/cli/src/utils/__tests__/send-message-helpers.test.ts
+++ b/cli/src/utils/__tests__/send-message-helpers.test.ts
@@ -1325,10 +1325,6 @@ describe('getAgentBaseName', () => {
   test('returns simple name unchanged', () => {
     expect(getAgentBaseName('file-picker')).toBe('file-picker')
   })
-
-  test('normalizes direct tool aliases to canonical agent names', () => {
-    expect(getAgentBaseName('code_reviewer_lite')).toBe('code-reviewer-lite')
-  })
 })
 
 describe('agentTypesMatch', () => {
diff --git a/cli/src/utils/message-block-helpers.ts b/cli/src/utils/message-block-helpers.ts
index 2d0eb29fe..b9668da41 100644
--- a/cli/src/utils/message-block-helpers.ts
+++ b/cli/src/utils/message-block-helpers.ts
@@ -16,11 +16,10 @@ import type {
  * getAgentBaseName('codebuff/file-picker@0.0.2') // 'file-picker'
  * getAgentBaseName('file-picker@1.0.0') // 'file-picker'
  * getAgentBaseName('file-picker') // 'file-picker'
- * getAgentBaseName('file_picker') // 'file-picker'
  */
 export const getAgentBaseName = (type: string): string => {
   const segment = type.split('/').pop() ?? type
-  return segment.split('@')[0].replace(/_/g, '-')
+  return segment.split('@')[0]
 }
 
 /**
@@ -467,7 +466,6 @@ export const moveSpawnAgentBlock = (
   parentId?: string,
   params?: Record<string, unknown>,
   prompt?: string,
-  realAgentType?: string,
 ): ContentBlock[] => {
   const updateAgentBlock = (block: ContentBlock): ContentBlock => {
     if (block.type !== 'agent') {
@@ -486,11 +484,6 @@ export const moveSpawnAgentBlock = (
       updatedBlock.initialPrompt = prompt
     }
 
-    if (realAgentType) {
-      updatedBlock.agentType = realAgentType
-      updatedBlock.agentName = realAgentType
-    }
-
     return updatedBlock
   }
 
diff --git a/cli/src/utils/sdk-event-handlers.ts b/cli/src/utils/sdk-event-handlers.ts
index 42c273a82..6f304f147 100644
--- a/cli/src/utils/sdk-event-handlers.ts
+++ b/cli/src/utils/sdk-event-handlers.ts
@@ -183,7 +183,6 @@ const handleSubagentStart = (
         blocks,
         match: spawnAgentMatch,
         realAgentId: event.agentId,
-        realAgentType: event.agentType,
         parentAgentId: event.parentAgentId,
         params: event.params,
         prompt: event.prompt,
diff --git a/cli/src/utils/spawn-agent-matcher.ts b/cli/src/utils/spawn-agent-matcher.ts
index a87e493b1..c3eb5c054 100644
--- a/cli/src/utils/spawn-agent-matcher.ts
+++ b/cli/src/utils/spawn-agent-matcher.ts
@@ -28,7 +28,6 @@ export const resolveSpawnAgentToReal = (options: {
   blocks: ContentBlock[]
   match: SpawnAgentMatch
   realAgentId: string
-  realAgentType?: string
   parentAgentId?: string
   params?: Record<string, unknown>
   prompt?: string
@@ -37,7 +36,6 @@ export const resolveSpawnAgentToReal = (options: {
     blocks,
     match,
     realAgentId,
-    realAgentType,
     parentAgentId,
     params: agentParams,
     prompt,
@@ -50,6 +48,5 @@ export const resolveSpawnAgentToReal = (options: {
     parentAgentId,
     agentParams,
     prompt,
-    realAgentType,
   )
 }
diff --git a/freebuff/cli/release/package.json b/freebuff/cli/release/package.json
index 55a51a2cc..0b810c657 100644
--- a/freebuff/cli/release/package.json
+++ b/freebuff/cli/release/package.json
@@ -1,6 +1,6 @@
 {
   "name": "freebuff",
-  "version": "0.0.80",
+  "version": "0.0.82",
   "description": "The world's strongest free coding agent",
   "license": "MIT",
   "bin": {
diff --git a/packages/agent-runtime/src/__tests__/run-programmatic-step.test.ts b/packages/agent-runtime/src/__tests__/run-programmatic-step.test.ts
index 5a06372e0..954bdc73f 100644
--- a/packages/agent-runtime/src/__tests__/run-programmatic-step.test.ts
+++ b/packages/agent-runtime/src/__tests__/run-programmatic-step.test.ts
@@ -212,28 +212,6 @@ describe('runProgrammaticStep', () => {
   })
 
   describe('tool execution', () => {
-    it('assigns deterministic per-tool ids to handleSteps tool calls', async () => {
-      const mockGenerator = (function* () {
-        yield { toolName: 'read_files', input: { paths: ['first.txt'] } }
-        yield { toolName: 'read_files', input: { paths: ['second.txt'] } }
-        yield { toolName: 'end_turn', input: {} }
-      })() as StepGenerator
-
-      mockTemplate.handleSteps = () => mockGenerator
-
-      await runProgrammaticStep(mockParams)
-
-      expect(executeToolCallSpy.mock.calls[0][0].toolCallId).toBe(
-        'functions.read_files:0',
-      )
-      expect(executeToolCallSpy.mock.calls[1][0].toolCallId).toBe(
-        'functions.read_files:1',
-      )
-      expect(executeToolCallSpy.mock.calls[2][0].toolCallId).toBe(
-        'functions.end_turn:0',
-      )
-    })
-
     it('should not add tool call message for add_message tool', async () => {
       const mockGenerator = (function* () {
         yield {
diff --git a/packages/agent-runtime/src/__tests__/tool-validation-error.test.ts b/packages/agent-runtime/src/__tests__/tool-validation-error.test.ts
index 520b4d087..c07ce42cb 100644
--- a/packages/agent-runtime/src/__tests__/tool-validation-error.test.ts
+++ b/packages/agent-runtime/src/__tests__/tool-validation-error.test.ts
@@ -464,7 +464,6 @@ describe('tool validation error handling', () => {
     )
     expect(toolCallEvents.length).toBe(1)
     expect(toolCallEvents[0].toolName).toBe('read_files')
-    expect(toolCallEvents[0].toolCallId).toBe('functions.read_files:0')
 
     // Verify tool_result event was emitted
     const toolResultEvents = responseChunks.filter(
@@ -472,8 +471,6 @@ describe('tool validation error handling', () => {
         typeof chunk !== 'string' && chunk.type === 'tool_result',
     )
     expect(toolResultEvents.length).toBe(1)
-    expect(toolResultEvents[0].toolName).toBe('read_files')
-    expect(toolResultEvents[0].toolCallId).toBe('functions.read_files:0')
 
     // Verify NO error events
     const errorEvents = responseChunks.filter(
diff --git a/packages/agent-runtime/src/run-programmatic-step.ts b/packages/agent-runtime/src/run-programmatic-step.ts
index 83bd94368..64addd410 100644
--- a/packages/agent-runtime/src/run-programmatic-step.ts
+++ b/packages/agent-runtime/src/run-programmatic-step.ts
@@ -6,7 +6,7 @@ import { cloneDeep } from 'lodash'
 import { clearProposedContentForRun } from './tools/handlers/tool/proposed-content-store'
 import { executeToolCall } from './tools/tool-executor'
 import { parseTextWithToolCalls } from './util/parse-tool-calls-from-text'
-import { createToolCallIdGenerator } from './util/tool-call-id'
+
 
 import type { FileProcessingState } from './tools/handlers/tool/write-file'
 import type { ExecuteToolCallParams } from './tools/tool-executor'
@@ -213,7 +213,6 @@ export async function runProgrammaticStep(
   let toolResult: ToolResultOutput[] | undefined = undefined
   let endTurn = false
   let generateN: number | undefined = undefined
-  const getToolCallId = createToolCallIdGenerator(agentState.messageHistory)
 
   let startTime = new Date()
   let creditsBefore = agentState.directCreditsUsed
@@ -274,7 +273,6 @@ export async function runProgrammaticStep(
             previousToolCallFinished: Promise.resolve(),
             toolCalls,
             toolResults,
-            getToolCallId,
             onResponseChunk,
           })
         }
@@ -303,7 +301,6 @@ export async function runProgrammaticStep(
         previousToolCallFinished: Promise.resolve(),
         toolCalls,
         toolResults,
-        getToolCallId,
         onResponseChunk,
       })
 
@@ -435,7 +432,6 @@ type ExecuteToolCallsArrayParams = Omit<
   | 'toolResultsToAddToMessageHistory'
 > & {
   agentState: AgentState
-  getToolCallId: (toolName: string) => string
   onResponseChunk: (chunk: string | PrintModeEvent) => void
 }
 
@@ -449,7 +445,7 @@ async function executeSingleToolCall(
   toolCallToExecute: ToolCallToExecute,
   params: ExecuteToolCallsArrayParams,
 ): Promise<ToolResultOutput[] | undefined> {
-  const { agentState, getToolCallId, onResponseChunk, toolResults } = params
+  const { agentState, onResponseChunk, toolResults } = params
 
   // Note: We don't check if the tool is available for the agent template anymore.
   // You can run any tool from handleSteps now!
@@ -459,7 +455,7 @@ async function executeSingleToolCall(
   //   )
   // }
 
-  const toolCallId = getToolCallId(toolCallToExecute.toolName)
+  const toolCallId = crypto.randomUUID()
   const excludeToolFromMessageHistory =
     toolCallToExecute.includeToolCall === false
 
diff --git a/packages/agent-runtime/src/tool-stream-parser.ts b/packages/agent-runtime/src/tool-stream-parser.ts
index 1f4deed9d..cd4ca58df 100644
--- a/packages/agent-runtime/src/tool-stream-parser.ts
+++ b/packages/agent-runtime/src/tool-stream-parser.ts
@@ -50,6 +50,7 @@ export async function* processStreamWithTools(params: {
   }
   trackEvent: TrackEventFn
   executeXmlToolCall: (params: {
+    toolCallId: string
     toolName: string
     input: Record<string, unknown>
   }) => Promise<void>
@@ -149,9 +150,12 @@ export async function* processStreamWithTools(params: {
 
       // Then process and yield any XML tool calls found
       for (const toolCall of toolCalls) {
+        const toolCallId = `xml-${crypto.randomUUID().slice(0, 8)}`
+
         // Execute the tool immediately if callback provided, pausing the stream
         // The callback handles emitting tool_call and tool_result events
         await executeXmlToolCall({
+          toolCallId,
           toolName: toolCall.toolName,
           input: toolCall.input,
         })
diff --git a/packages/agent-runtime/src/tools/stream-parser.ts b/packages/agent-runtime/src/tools/stream-parser.ts
index fd8f9ea0c..4cdb32117 100644
--- a/packages/agent-runtime/src/tools/stream-parser.ts
+++ b/packages/agent-runtime/src/tools/stream-parser.ts
@@ -5,6 +5,7 @@ import {
   assistantMessage,
   userMessage,
 } from '@codebuff/common/util/messages'
+import { generateCompactId } from '@codebuff/common/util/string'
 
 import { processStreamWithTools } from '../tool-stream-parser'
 import { INCLUDE_REASONING_IN_MESSAGE_HISTORY } from '../constants'
@@ -13,7 +14,6 @@ import {
   executeToolCall,
   tryTransformAgentToolCall,
 } from './tool-executor'
-import { createToolCallIdGenerator } from '../util/tool-call-id'
 import { withSystemTags } from '../util/messages'
 
 import type { CustomToolCall, ExecuteToolCallParams } from './tool-executor'
@@ -91,7 +91,6 @@ export async function processStream(
   const toolCalls: (CodebuffToolCall | CustomToolCall)[] = []
   const toolCallsToAddToMessageHistory: (CodebuffToolCall | CustomToolCall)[] = []
   const assistantMessages: Message[] = []
-  const getToolCallId = createToolCallIdGenerator(params.messages)
   let hadToolCallError = false
   const errorMessages: Message[] = []
   const { promise: streamDonePromise, resolve: resolveStreamDonePromise } =
@@ -138,6 +137,7 @@ export async function processStream(
         if (signal.aborted) {
           return
         }
+        const toolCallId = generateCompactId()
         const isNativeTool = toolNames.includes(toolName as ToolName)
 
         // Check if this is an agent tool call that should be transformed to spawn_agents
@@ -160,20 +160,19 @@ export async function processStream(
         // Determine which executor to use and with what parameters
         let toolPromise: Promise<void>
         if (isNativeTool || transformed) {
-          const effectiveToolName = transformed
-            ? transformed.toolName
-            : (toolName as ToolName)
           // Use executeToolCall for native tools or transformed agent calls
           toolPromise = executeToolCall({
             ...params,
-            toolName: effectiveToolName,
+            toolName: transformed
+              ? transformed.toolName
+              : (toolName as ToolName),
             input: transformed ? transformed.input : input,
             fromHandleSteps: false,
 
             fileProcessingState,
             fullResponse: fullResponseChunks.join(''),
             previousToolCallFinished: previousPromise,
-            toolCallId: getToolCallId(effectiveToolName),
+            toolCallId,
             toolCalls,
             toolCallsToAddToMessageHistory,
             toolResults,
@@ -192,7 +191,7 @@ export async function processStream(
             fileProcessingState,
             fullResponse: fullResponseChunks.join(''),
             previousToolCallFinished: previousPromise,
-            toolCallId: getToolCallId(toolName),
+            toolCallId,
             toolCalls,
             toolCallsToAddToMessageHistory,
             toolResults,
diff --git a/packages/agent-runtime/src/tools/tool-executor.ts b/packages/agent-runtime/src/tools/tool-executor.ts
index f50e8823c..8fd7130bf 100644
--- a/packages/agent-runtime/src/tools/tool-executor.ts
+++ b/packages/agent-runtime/src/tools/tool-executor.ts
@@ -1,13 +1,12 @@
 import { endsAgentStepParam, toolNames } from '@codebuff/common/tools/constants'
 import { toolParams } from '@codebuff/common/tools/list'
-import { normalizeAgentIdForLookup } from '@codebuff/common/util/agent-id-parsing'
+import { generateCompactId } from '@codebuff/common/util/string'
 import { cloneDeep } from 'lodash'
 
 import { getMCPToolData } from '../mcp'
 import { MCP_TOOL_SEPARATOR } from '../mcp-constants'
 import { getAgentShortName, getAgentToolName } from '../templates/prompts'
 import { formatValueForError } from '../util/format-value'
-import { createToolCallIdGenerator } from '../util/tool-call-id'
 import { codebuffToolHandlers } from './handlers/list'
 import { getMatchingSpawn } from './handlers/tool/spawn-agent-utils'
 import { getAgentTemplate } from '../templates/agent-registry'
@@ -309,9 +308,7 @@ export async function executeToolCall<T extends ToolName>(
     onResponseChunk,
     requestToolCall,
   } = params
-  const toolCallId =
-    params.toolCallId ??
-    createToolCallIdGenerator(agentState.messageHistory, toolCalls)(toolName)
+  const toolCallId = params.toolCallId ?? generateCompactId()
 
   const toolCall: CodebuffToolCall<T> | ToolCallError = parseRawToolCall<T>({
     rawToolCall: {
@@ -372,9 +369,7 @@ export async function executeToolCall<T extends ToolName>(
             }
           }
 
-          let agentIdToLoad = isBaseAgent
-            ? normalizeAgentIdForLookup(agentTypeStr)
-            : agentTypeStr
+          let agentIdToLoad = agentTypeStr
           if (!isBaseAgent) {
             const matchingSpawn = getMatchingSpawn(
               agentTemplate.spawnableAgents,
@@ -423,13 +418,7 @@ export async function executeToolCall<T extends ToolName>(
             }
           }
 
-          return {
-            valid: true as const,
-            agent: {
-              ...(agent as Record<string, unknown>),
-              agent_type: agentIdToLoad,
-            },
-          }
+          return { valid: true as const, agent }
         }),
       )
 
@@ -458,8 +447,8 @@ export async function executeToolCall<T extends ToolName>(
         }
         const errorMsg = `Some agents could not be spawned: ${errors.join('; ')}. Proceeding with valid agents only.`
         onResponseChunk({ type: 'error', message: errorMsg })
+        effectiveInput = { ...effectiveInput, agents: validAgents }
       }
-      effectiveInput = { ...effectiveInput, agents: validAgents }
     }
   }
 
@@ -651,11 +640,7 @@ export async function executeCustomToolCall(
     }),
     rawToolCall: {
       toolName,
-      toolCallId:
-        toolCallId ??
-        createToolCallIdGenerator(agentState.messageHistory, toolCalls)(
-          toolName,
-        ),
+      toolCallId: toolCallId ?? generateCompactId(),
       input,
     },
     autoInsertEndStepParam,
diff --git a/packages/agent-runtime/src/util/__tests__/tool-call-id.test.ts b/packages/agent-runtime/src/util/__tests__/tool-call-id.test.ts
deleted file mode 100644
index 21a150f63..000000000
--- a/packages/agent-runtime/src/util/__tests__/tool-call-id.test.ts
+++ /dev/null
@@ -1,63 +0,0 @@
-import { assistantMessage } from '@codebuff/common/util/messages'
-import { describe, expect, it } from 'bun:test'
-
-import {
-  countToolCallsByName,
-  createToolCallIdGenerator,
-  formatToolCallId,
-} from '../tool-call-id'
-
-describe('tool call ids', () => {
-  it('formats ids with the tool name and per-tool invocation index', () => {
-    expect(formatToolCallId('glob', 0)).toBe('functions.glob:0')
-  })
-
-  it('seeds per-tool counters from existing message history', () => {
-    const messages = [
-      assistantMessage({
-        type: 'tool-call',
-        toolName: 'glob',
-        toolCallId: 'functions.glob:0',
-        input: { pattern: '**/*.ts' },
-      }),
-      assistantMessage({
-        type: 'tool-call',
-        toolName: 'read_files',
-        toolCallId: 'functions.read_files:0',
-        input: { paths: ['src/index.ts'] },
-      }),
-      assistantMessage({
-        type: 'tool-call',
-        toolName: 'glob',
-        toolCallId: 'functions.glob:1',
-        input: { pattern: '**/*.tsx' },
-      }),
-    ]
-
-    expect(countToolCallsByName(messages)).toEqual(
-      new Map([
-        ['glob', 2],
-        ['read_files', 1],
-      ]),
-    )
-
-    const getToolCallId = createToolCallIdGenerator(messages)
-
-    expect(getToolCallId('glob')).toBe('functions.glob:2')
-    expect(getToolCallId('glob')).toBe('functions.glob:3')
-    expect(getToolCallId('read_files')).toBe('functions.read_files:1')
-  })
-
-  it('can seed counters from pending tool calls', () => {
-    const getToolCallId = createToolCallIdGenerator([], [
-      {
-        toolName: 'glob',
-      },
-      {
-        toolName: 'glob',
-      },
-    ])
-
-    expect(getToolCallId('glob')).toBe('functions.glob:2')
-  })
-})
diff --git a/packages/agent-runtime/src/util/tool-call-id.ts b/packages/agent-runtime/src/util/tool-call-id.ts
deleted file mode 100644
index bfa64f150..000000000
--- a/packages/agent-runtime/src/util/tool-call-id.ts
+++ /dev/null
@@ -1,48 +0,0 @@
-import type { Message } from '@codebuff/common/types/messages/codebuff-message'
-
-const TOOL_CALL_ID_PREFIX = 'functions'
-type ToolCallLike = { toolName: string }
-
-export function formatToolCallId(toolName: string, index: number): string {
-  return `${TOOL_CALL_ID_PREFIX}.${toolName}:${index}`
-}
-
-export function countToolCallsByName(
-  messages: Message[],
-  pendingToolCalls: ToolCallLike[] = [],
-): Map<string, number> {
-  const counts = new Map<string, number>()
-
-  for (const message of messages) {
-    if (message.role !== 'assistant') {
-      continue
-    }
-
-    for (const part of message.content) {
-      if (part.type !== 'tool-call') {
-        continue
-      }
-
-      counts.set(part.toolName, (counts.get(part.toolName) ?? 0) + 1)
-    }
-  }
-
-  for (const toolCall of pendingToolCalls) {
-    counts.set(toolCall.toolName, (counts.get(toolCall.toolName) ?? 0) + 1)
-  }
-
-  return counts
-}
-
-export function createToolCallIdGenerator(
-  messages: Message[],
-  pendingToolCalls: ToolCallLike[] = [],
-) {
-  const counts = countToolCallsByName(messages, pendingToolCalls)
-
-  return (toolName: string): string => {
-    const index = counts.get(toolName) ?? 0
-    counts.set(toolName, index + 1)
-    return formatToolCallId(toolName, index)
-  }
-}