Refactor helper for surfacing original tool call in error message

Author: jahooma

packages/agent-runtime/src/tools/handlers/tool/set-output.ts

@@ -1,6 +1,7 @@
 import { jsonToolResult } from '@codebuff/common/util/messages'
 
 import { getAgentTemplate } from '../../../templates/agent-registry'
+import { formatValueForError } from '../../../util/format-value'
 
 import type { CodebuffToolHandlerFunction } from '../handler-function-type'
 import type {
@@ -61,11 +62,7 @@ export const handleSetOutput = (async (params: {
         const prefix = usedData
           ? 'Output validation error: Your output was found inside the `data` field but still failed validation. Please fix the issues and try again without wrapping in `data`. Issues: '
           : 'Output validation error: Output failed to match the output schema and was ignored. You might want to try again! Issues: '
-        const outputStr = JSON.stringify(output, null, 2)
-        const truncatedOutput = outputStr.length > 500
-          ? outputStr.slice(0, 500) + '...(truncated)'
-          : outputStr
-        const errorMessage = `${prefix}${bestError}\n\nOriginal output value:\n${truncatedOutput}`
+        const errorMessage = `${prefix}${bestError}\n\nOriginal output value:\n${formatValueForError(output)}`
         logger.error(
           {
             output,

packages/agent-runtime/src/tools/handlers/tool/spawn-agent-utils.ts

@@ -5,6 +5,7 @@ import { generateCompactId } from '@codebuff/common/util/string'
 
 import { loopAgentSteps } from '../../../run-agent-step'
 import { getAgentTemplate } from '../../../templates/agent-registry'
+import { formatValueForError } from '../../../util/format-value'
 import {
   filterUnfinishedToolCalls,
   withSystemTags,
@@ -221,12 +222,8 @@ export function validateAgentInput(
   if (inputSchema.prompt) {
     const result = inputSchema.prompt.safeParse(prompt ?? '')
     if (!result.success) {
-      const promptStr = JSON.stringify(prompt ?? '', null, 2)
-      const truncatedPrompt = promptStr.length > 500
-        ? promptStr.slice(0, 500) + '...(truncated)'
-        : promptStr
       throw new Error(
-        `Invalid prompt for agent ${agentType}: ${JSON.stringify(result.error.issues, null, 2)}\n\nOriginal prompt value:\n${truncatedPrompt}`,
+        `Invalid prompt for agent ${agentType}: ${JSON.stringify(result.error.issues, null, 2)}\n\nOriginal prompt value:\n${formatValueForError(prompt ?? '')}`,
       )
     }
   }
@@ -235,12 +232,8 @@ export function validateAgentInput(
   if (inputSchema.params) {
     const result = inputSchema.params.safeParse(params ?? {})
     if (!result.success) {
-      const paramsStr = JSON.stringify(params ?? {}, null, 2)
-      const truncatedParams = paramsStr.length > 500
-        ? paramsStr.slice(0, 500) + '...(truncated)'
-        : paramsStr
       throw new Error(
-        `Invalid params for agent ${agentType}: ${JSON.stringify(result.error.issues, null, 2)}\n\nOriginal params value:\n${truncatedParams}`,
+        `Invalid params for agent ${agentType}: ${JSON.stringify(result.error.issues, null, 2)}\n\nOriginal params value:\n${formatValueForError(params ?? {})}`,
       )
     }
   }

packages/agent-runtime/src/tools/tool-executor.ts

@@ -6,6 +6,7 @@ import { cloneDeep } from 'lodash'
 import { getMCPToolData } from '../mcp'
 import { MCP_TOOL_SEPARATOR } from '../mcp-constants'
 import { getAgentShortName } from '../templates/prompts'
+import { formatValueForError } from '../util/format-value'
 import { codebuffToolHandlers } from './handlers/list'
 import {
   getMatchingSpawn,
@@ -180,13 +181,10 @@ export async function executeToolCall<T extends ToolName>(
   }
 
   if ('error' in toolCall) {
-    const inputStr = JSON.stringify(input, null, 2)
-    const truncatedInput = inputStr.length > 500
-      ? inputStr.slice(0, 500) + '...(truncated)'
-      : inputStr
+    const formattedInput = formatValueForError(input)
     onResponseChunk({
       type: 'error',
-      message: `${toolCall.error}\n\nOriginal tool call input:\n${truncatedInput}`,
+      message: `${toolCall.error}\n\nOriginal tool call input:\n${formattedInput}`,
     })
     logger.debug(
       { toolCall, error: toolCall.error },
@@ -491,13 +489,10 @@ export async function executeCustomToolCall(
   }
 
   if ('error' in toolCall) {
-    const inputStr = JSON.stringify(input, null, 2)
-    const truncatedInput = inputStr.length > 500
-      ? inputStr.slice(0, 500) + '...(truncated)'
-      : inputStr
+    const formattedInput = formatValueForError(input)
     onResponseChunk({
       type: 'error',
-      message: `${toolCall.error}\n\nOriginal tool call input:\n${truncatedInput}`,
+      message: `${toolCall.error}\n\nOriginal tool call input:\n${formattedInput}`,
     })
     logger.debug(
       { toolCall, error: toolCall.error },

packages/agent-runtime/src/util/format-value.ts

@@ -0,0 +1,10 @@
+export function formatValueForError(value: unknown, maxLength = 500): string {
+  const jsonStr = JSON.stringify(value, null, 2) ?? 'undefined'
+  const truncated = jsonStr.length > maxLength
+    ? jsonStr.slice(0, maxLength) + '...(truncated)'
+    : jsonStr
+  if (value === null || value === undefined || typeof value !== 'object') {
+    return `${truncated} (type: ${value === null ? 'null' : typeof value})`
+  }
+  return truncated
+}