How do you link Scores to a Prompt

[ogirardot]

I tried to start an evaluator observation (linked to a root trace) and set the prompt there, but the prompt is not linked and none of the scores added end up on the prompt version. What am I missing ?

[inkeep-ai-assistant[bot]]

Based on the provided documentation, scores in Langfuse are linked to traces, observations, sessions, or dataset runs - not directly to prompts(1).

Scores can be:

• Associated with a trace, session, or dataset run (one and only one is required)(1)
• For trace-level scores only: linked to a specific observation within a trace (optional)(1)

The documentation indicates that to link prompt management with tracing, you should check the FAQ entry "Link prompt management with tracing in Langfuse"(2). This suggests there's a specific approach for connecting prompts to traces and their associated scores.

If you want scores to appear on a prompt version, you likely need to:

1. Link the prompt to the trace itself (not just an observation)
2. Add scores to the trace that used that prompt version

The evaluator observation approach you mentioned won't automatically link scores to the prompt version because scores are attached to the trace/observation/session level, not to prompts directly(1).

For more specific guidance on linking prompts with tracing and evaluation, I'd recommend checking the detailed FAQ on this topic referenced in the documentation(2).

📚 Sources:

1. Observability Data Model
2. Troubleshooting and FAQ

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[jannikmaierhoefer]

Hi @ogirardot, to clarify, you are using in-UI Langfuse Dataset Experiments or are you tracing your application and currently cant see the linked prompt?