Langfuse Trace View

Display detailed information for a specific trace.

Setup

Set the following environment variables before use:

When to Use

• Checking specific trace details
• Viewing LLM input/output
• "Show me the details of this trace"
• Investigating by trace ID

Commands

1. Get Trace Details

npx tsx scripts/langfuse-trace-view.ts <traceId>

2. JSON Output

npx tsx scripts/langfuse-trace-view.ts <traceId> --json

Output Example

Langfuse Trace Detail
=====================

ID:        abc123-def456-ghi789
Name:      librarian/chat
Timestamp: 2025-01-15 10:30:45
User ID:   user-123
Session:   lb:session-456
Latency:   1234ms
Cost:      $0.0150
Tags:      env:production

Metadata:
{
  "projectId": "project-123",
  "organizationId": "org-456"
}

Input:
{
  "userMessage": "Search the knowledge base"
}

Output:
{
  "response": "Here are the search results..."
}

Observations (3):
--------------------------------------------------------------------------------

[GENERATION] llm-call
  Time: 10:30:46  Model: gpt-4o  Cost: $0.0120  Tokens: in:150 out:200
  Input: {"role": "user", ...}
  Output: Here are the search results...

[SPAN] tool-execution
  Time: 10:30:47  Model: -  Cost: -  Tokens: -

Fields