# Langfuse MCP

Vendor: Langfuse  
Category: developer-tools  
Auth: API_KEY  
Composio slug: `langfuse`

Open source LLM engineering platform. Traces, evals, prompt management and metrics to debug and improve your LLM application.

## Tools

- **Create Score** — Attach an evaluation score to exactly one Langfuse trace, session, or dataset run, optionally narrowing a trace score to an observation.
- **Get Annotation Queue** — Retrieve one Langfuse annotation queue by its ID.
- **Get Prompt** — Retrieve a Langfuse text or chat prompt by name, deployment label, or exact version, with optional dependency resolution.
- **List Annotation Queues** — List annotation queues configured for human evaluation in the connected Langfuse project.
- **List Dataset Items** — List dataset items, optionally scoped to a dataset, source trace or observation, or historical dataset version.
- **List Dataset Run Items** — List run items for a specific Langfuse dataset and run name.
- **List Datasets** — List datasets available to the connected Langfuse project.
- **List Experiments** — List Langfuse experiments active in a required time range, optionally including metadata and directly attached scores.
- **List Models** — List Langfuse-managed and project-custom model pricing definitions used for usage and cost calculation.
- **List Observations** — Search Langfuse observations such as generations, spans, events, agents, and tool calls, selecting only the field groups needed.
- **List Scores** — Search numeric, boolean, categorical, text, and correction scores with subject and annotation context.
- **Query Metrics** — Run an aggregate Langfuse metrics query over observations or numeric, boolean, or categorical scores.
- **Upsert LLM Connection** — Create or update a Langfuse LLM provider connection by provider name.

## Setup

1. Create or open a Switchy Project.
2. Open Integrations and connect Langfuse.
3. Authorise through api_key.
4. Teammates can now @-mention Langfuse tools in chat.

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Last verified: 2026-09-03T02:00:04.194Z  
Canonical URL: https://switchy.build/directory/mcps/langfuse