Langfuse MCP Server
Server Configuration
Describes the environment variables required to run the server.
| Name | Required | Description | Default |
|---|---|---|---|
| LANGFUSE_HOST | No | Langfuse instance URL. Use your instance URL if self-hosted. Can also be supplied via the --host CLI flag. Defaults to https://cloud.langfuse.com. | https://cloud.langfuse.com |
| LANGFUSE_PUBLIC_KEY | No | Langfuse public API key (pk-...), from Langfuse Cloud → Settings → API Keys. Can also be supplied via the --public-key CLI flag. | |
| LANGFUSE_SECRET_KEY | No | Langfuse secret API key (sk-...), from Langfuse Cloud → Settings → API Keys. Can also be supplied via the --secret-key CLI flag. | |
| LANGFUSE_MCP_PROFILE | No | Profile to load from the profiles file; same as the --profile CLI flag. Selects a profile when --profile is not given. Used to register one MCP server per Langfuse project. | |
| LANGFUSE_MAX_AGE_DAYS | No | Caps the lookback window for time-based tools (fetch_traces, fetch_observations, etc.). Set to match your Langfuse instance's data retention — e.g. 30 if your retention is 30 days. | 7 |
| LANGFUSE_MCP_READ_ONLY | No | Set to true to disable all write operations for safer read-only access; same as the --read-only CLI flag. | false |
| LANGFUSE_MCP_PROFILES_FILE | No | Path of the TOML profiles file; same as the --profiles-file CLI flag. Defaults to $XDG_CONFIG_HOME/langfuse-mcp/profiles.toml (or ~/.config/langfuse-mcp/profiles.toml when XDG_CONFIG_HOME is not set). | $XDG_CONFIG_HOME/langfuse-mcp/profiles.toml |
| LANGFUSE_MCP_DEFAULT_OUTPUT_MODE | No | Sets the MCP-exposed default output_mode so clients that omit the parameter automatically use your preferred mode; same as the --default-output-mode CLI flag. Supported values: compact, full_json_string, full_json_file. | compact |
| LANGFUSE_MCP_TRACE_TIMEOUT_SECONDS | No | Per-request read timeout (seconds) for single-trace fetches (fetch_trace). Raise it if large traces with include_observations=True time out. Must be a positive integer. | 120 |
Instructions
Guidance the server publishes about itself, which clients place ahead of the tool catalog so the model reads it before choosing anything.
This server publishes no instructions, or was last inspected before Glama recorded them.
Capabilities
Server capabilities have not been inspected yet.
Tools
Functions exposed to the LLM to take actions
| Name | Description |
|---|---|
No tools | |
Prompts
Interactive templates invoked by user choice
| Name | Description |
|---|---|
No prompts | |
Resources
Contextual data attached and managed by the client
| Name | Description |
|---|---|
No resources | |
This server cannot be deployed
Maintenance
ActivityActive
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