Vercel 'ai' Cannot be instrumented

[dested]

It seems something has changed in the implementation since this instrumentation was released. Any help would be appreciated!

Uncaught Exception: TypeError: Cannot redefine property: generateText
    at Function.defineProperty (<anonymous>)
    at defineProperty (C:\code\shopd\api\node_modules\shimmer\index.js:14:10)
    at wrap (C:\code\shopd\api\node_modules\shimmer\index.js:56:3)
    at VercelAIInstrumentation.InstrumentationBase._wrap (C:\code\shopd\api\node_modules\@langtrase\typescript-sdk\node_modules\@opentelemetry\instrumentation\src\platform\node\instrumentation.ts:77:18)
    at VercelAIInstrumentation._patch (C:\code\shopd\api\node_modules\@langtrase\typescript-sdk\src\instrumentation\vercel\instrumentation.ts:37:10)
    at VercelAIInstrumentation.manualPatch (C:\code\shopd\api\node_modules\@langtrase\typescript-sdk\src\instrumentation\vercel\instrumentation.ts:14:10)
    at C:\code\shopd\api\node_modules\@langtrase\typescript-sdk\src\init\init.ts:207:44
    at Array.forEach (<anonymous>)
    at Object.init (C:\code\shopd\api\node_modules\@langtrase\typescript-sdk\src\init\init.ts:205:38)

[karthikscale3]

Hi, thanks for reporting this. We will take a look and get back to you as soon as possible.

[alizenhom]

Hey @dested, apologies for the issue you're facing

can you try initializing Langtrace at the top of your code before any imports?
this might rule out some scenarios

also if it's okay with you can you share the code snippet you're running in order to be able to replicate faster?
apologies again will work on this issue with high priority

[olascale3]

🔍 Triage Assessment

Priority: High
Category: Bug - Vercel AI SDK Integration
Impact: Critical - Cannot instrument Vercel AI SDK due to property redefinition error

Root Cause Analysis:
The error Cannot redefine property: generateText suggests that the Vercel AI SDK's generateText function is already being instrumented or modified by another library, or the property descriptor doesn't allow redefinition.

Technical Details:

• Error occurs in shimmer library when trying to wrap the generateText function
• This indicates a conflict in property definition/instrumentation approach
• May be related to changes in Vercel AI SDK's internal structure

Recommended Fix:

1. Check if generateText property is configurable before attempting to wrap
2. Use alternative instrumentation approaches (monkey patching, proxy patterns)
3. Update instrumentation to handle non-configurable properties gracefully
4. Test with latest Vercel AI SDK versions

Next Steps:

• Investigate current Vercel AI SDK property descriptors
• Implement defensive property checking before wrapping
• Add fallback instrumentation methods
• Update compatibility testing

This is blocking users from using Langtrace with Vercel AI, which is a popular framework.

[olascale3]

Triage Notes:

• Type: Bug - Critical
• Priority: High
• Area: Vercel AI SDK instrumentation
• Labels needed: bug, vercel-ai, high-priority, instrumentation

Critical bug preventing instrumentation of Vercel 'ai' package due to property redefinition error. This suggests a breaking change in the Vercel AI SDK that conflicts with our shimmer-based instrumentation.

Error: Cannot redefine property: generateText

Action Required: High priority fix needed - update instrumentation approach for newer Vercel AI SDK versions.

[olascale3]

Triage Assessment

Priority: High
Category: Bug - Vercel AI Integration
Labels Needed: bug, vercel-ai, priority:high

Analysis: Critical runtime error preventing Vercel AI instrumentation. The error "Cannot redefine property: generateText" suggests the instrumentation is trying to wrap a property that's already been modified or is non-configurable. This breaks a popular integration.

Next Steps:

1. URGENT: Update Vercel AI instrumentation to handle property redefinition
2. Check for existing instrumentation before wrapping
3. Test with latest Vercel AI SDK versions
4. Review shimmer wrapping approach