[BUG] Langfuseexporter fails on json response

[Alex793x]

Describe the bug

When running with langfuse exporter, we suddenly started experiencing following error in the voltagent debug logs:

[Langfuse SDK] Unknown error: 1738 | } catch (e) { 1739 | // fetch will only throw on network errors or on timeouts 1740 | throw new LangfuseFetchNetworkError(e); 1741 | } 1742 | if (res.status < 200 || res.status >= 400) { 1743 | const body = await res.json(); ^ SyntaxError: Failed to parse JSON at <anonymous> (/Users/alexthh/School/syncable-dev-rwii/fc-agent-voltagent/node_modules/langfuse-core/lib/index.mjs:1743:32)

Steps To Reproduce

1. setup langfuse exporter with public key and secret key
2. Setup a supervisor pattern or any agentic patterns/workflows
3. error should appear in-between tools utilization

Expected behavior

Expect to see tracing within the langfuse dashboard, but it never hits and we don't get any auth errors but json response errors

Packages

"@voltagent/core": "^1.1.23",
"@voltagent/langfuse-exporter": "^1.1.2",
"@voltagent/libsql": "^1.0.7",
"@voltagent/logger": "^1.0.2",
"@voltagent/server-hono": "1.0.15",
"@voltagent/vercel-ai": "^1.0.0",

Additional Context

No response

[omeraplak]

Hey @Alex793x ,
Thank you for the issue. We'll look into it soon.