// SCAN REPORT

Langfuse Observability

68 tools. 32 can modify or destroy data without limits.

8 destructive tools with no built-in limits. Policy required.

Last updated: 27 Jun 2026

32 can modify or destroy data

36 read-only

68 tools total

Community server · catalogue entry verified 27/06/2026

How to control Langfuse Observability ↓

TOOL MAP

What Langfuse Observability exposes to your agents

Read (36) Write / Execute (24) Destructive / Financial (8)

Running more than one server? Check your whole stack →

MOST DANGEROUS TOOLS

Critical Risk

The most dangerous Langfuse Observability tools

Destructive · High delete_calendar_event The tool permanently removes calendar event data without possibility of recovery through normal means. Destructive · High delete_mcp_json This tool permanently removes configuration data with no undo capability. Destructive · High delete_redirect This tool permanently deletes data (URL redirects) without the ability to undo the action. Destructive · High delete_unofficial_mirror This tool permanently removes data (unofficial mirrors) without the ability to undo the operation.

32 of Langfuse Observability's 68 tools can modify, destroy, or commit something on every call — and an agent calls them with no built-in limits.

POLICY

How to control Langfuse Observability

PolicyLayer is an MCP gateway — it sits between your AI agents and Langfuse Observability, and nothing reaches the server without passing your rules. These are the rules we recommend:

Deny destructive operations

{
  "delete_calendar_event": {
    "deny_if": [
      {
        "conditions": [],
        "on_deny": "Blocked by default. Requires approval."
      }
    ]
  }
}

Destructive tools should never be available to autonomous agents without human approval.

Rate limit write operations

{
  "add_message_to_thread": {
    "limits": [
      {
        "counter": "add_message_to_thread_per_hour",
        "window": "hour",
        "max": 30,
        "scope": "grant"
      }
    ]
  }
}

Prevents bulk unintended modifications from agents caught in loops.

Cap read operations

{
  "checkDeploy": {
    "limits": [
      {
        "counter": "checkdeploy_per_minute",
        "window": "minute",
        "max": 60,
        "scope": "grant"
      }
    ]
  }
}

Controls API costs and prevents retry loops from exhausting upstream rate limits.

Create a free account and register Langfuse Observability — nothing to install.
Add these rules — paste them, or build them visually. Tune the limits to your setup.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

ENFORCE POLICY ON LANGFUSE OBSERVABILITY →

Instant setup, no code required.

FULL CATALOGUE

All 68 Langfuse Observability tools

DESTRUCTIVE 8 tools

Destructive delete_calendar_event Deletes an event from Google Calendar. Destructive delete_mcp_json Delete an MCP JSON configuration by its ID. This action is irreversible. Use cases: - Remove obsolete configu Destructive delete_redirect Delete a URL redirect by its ID. This action is irreversible. Use cases: - Remove duplicate or outdated redir Destructive delete_unofficial_mirror Delete an unofficial mirror by its ID. This action is irreversible. Use cases: - Remove duplicate or outdated Destructive deleteEnvVars Delete one or more environment variables from your Rails application on Hatchbox. This tool uses the Hatchbox Destructive destroy_machine Delete a Fly.io machine. Permanently removes a Fly machine that was used for Proctor exam execution. Use this Destructive discard_good_job Discard a GoodJob background job. Marks the job as discarded so it will not be retried. Use cases: - Discard Destructive remove_servers_from_tenant Remove MCP servers from a tenant

EXECUTE 9 tools

Execute approve_official_mirror_queue_item Approve an official mirror queue entry and link it to an existing MCP server. This is an async operation that Execute cancel_exam Cancel a running Proctor exam. Stops an exam that is currently executing on a Fly machine. This is useful whe Execute force_trigger_good_job_cron Force trigger a GoodJob cron schedule immediately. Enqueues a new job for the specified cron schedule regardle Execute retry_good_job Retry a failed or discarded GoodJob background job. Re-enqueues the job for processing. Use cases: - Retry a Execute run_exam Execute a Proctor exam against an MCP server. Runs the specified exam using the provided runtime and MCP conf Execute run_exam_for_mirror Run proctor exams against unofficial mirrors to test their MCP server configurations. Proctor spins up Docker Execute set_popularity_drop_bypass Enable or disable a deliberate, auditable ONE-OFF bypass of the SYSTEMIC_DROP guardrail in the popularity-esti Execute ssh_execute Execute a command on the remote SSH server. Returns: JSON object with stdout, stderr, and exit code Use case Execute triggerDeploy Trigger a new deployment for your Rails application on Hatchbox. This tool initiates a deployment using Hatchb

WRITE 15 tools

Write add_message_to_thread Post a new message to an existing Twist thread. This tool allows you to contribute to ongoing conversations by Write add_official_mirror_to_regular_queue Add an official mirror queue entry to the regular MCP implementation queue. This creates a draft MCP implement Write add_servers_to_tenant Add MCP servers to a tenant Write approve_mirror_no_modify Approve an official mirror queue entry without modifying the linked MCP server. This is a synchronous operatio Write close_thread Close an existing Twist thread with an optional closing message. This tool marks a thread as closed, preventin Write create_calendar_event Creates a new event in Google Calendar. Write create_thread Create a new thread (conversation) in a Twist channel. Threads are the core organizational unit in Twist, allo Write mark_discovered_url_processed Mark a single discovered URL as processed after the agent has handled it. Sets processed_at to the current tim Write reject_official_mirror_queue_item Reject an official mirror queue entry. This is an async operation that enqueues a background job. This action Write save_results_for_mirror Save proctor exam results for an unofficial mirror. Pass the \ Write setEnvVar Set or update an environment variable for your Rails application on Hatchbox. This tool uses the Hatchbox API Write ssh_upload Upload a file from the local machine to the remote SSH server via SFTP. Returns: Success message with transfe Write switch_tenant_id Switch the active tenant ID used for all subsequent API requests. This is an admin tool for multi-tenant scena Write unlink_official_mirror_queue_item Unlink an official mirror queue entry from its linked MCP server. This is a synchronous operation. This actio Write update_calendar_event Updates an existing event in Google Calendar.

READ 36 tools

Read checkDeploy Check the status and progress of a deployment activity on Hatchbox. This tool retrieves real-time information Read find_airport_code Look up airport IATA codes by city name, airport name, or partial code. Use this to find the correct airport Read find_providers Find providers (organizations/individuals) in the PulseMCP registry. This tool can operate in two modes: 1. Read get_authors Retrieve a list of authors from the PulseMCP CMS who can create newsletter posts. Returns formatted markdown w Read get_calendar_event Retrieves detailed information about a specific calendar event by ID. Read get_channel Retrieve detailed information about a specific Twist channel along with its threads. This tool provides compre Read get_channels List all channels in your Twist workspace. Channels are the primary way to organize conversations in Twist, si Read get_date_grid Get a date-price grid for a route showing the lowest flight price for each day. Returns an array of dates wit Read get_diff_of_images Compare two images pixel-by-pixel and identify visual differences. Returns structured diff data including: - Read get_draft_mcp_implementations Retrieve a paginated list of draft MCP implementations from the PulseMCP Admin panel with all associated objec Read get_exam_result Retrieve the full, untruncated proctor exam result stored by a prior run_exam_for_mirror call. run_exam_for_m Read get_graphql_schema Returns a summary of the AppSignal GraphQL API schema, including available Query fields, Mutation fields, and Read get_graphql_schema_details Returns full GraphQL type definitions for the specified type names. Use this after get_graphql_schema to get d Read get_hotel_details Get detailed information about a specific hotel from Google Hotels via SerpAPI. Use this after search_hotels Read get_hotel_reviews Get individual guest reviews for a specific hotel from Google Hotels via SerpAPI. Use this after search_hotel Read get_machines List active Fly.io machines used for Proctor exams. Returns information about currently running or recently a Read get_newsletter_post Retrieve complete details for a specific newsletter post by its unique slug identifier. Returns formatted mark Read get_newsletter_posts Retrieve a paginated list of newsletter posts from the PulseMCP CMS. Returns formatted markdown with post summ Read get_official_mirror_queue_item Retrieve full details of a single official mirror queue entry by ID. Returns complete information including al Read get_official_mirror_queue_items Retrieve a paginated list of official mirror queue entries from the PulseMCP Admin panel. Returns formatted ma Read get_proctor_metadata Get available runtimes and exams for Proctor testing. Returns the list of available runtime environments (Doc Read get_server Get detailed information about a specific MCP server from the PulseMCP Sub-Registry. Returns the server\ Read get_thread Retrieve a complete thread conversation including all messages. This tool fetches the full context of a discus Read getEnvVar Retrieve a specific environment variable from your Rails application running on Hatchbox via SSH. This tool co Read getEnvVars Retrieve all environment variables from your Rails application running on Hatchbox via SSH. This tool connects Read list_calendar_events Lists events from a Google Calendar within an optional time range. Read list_calendars Lists all calendars available to the authenticated user. Read list_servers Browse MCP servers from the PulseMCP Sub-Registry. Returns a paginated list of active and deprecated servers w Read list_tenant_servers List a tenant Read query_calendar_freebusy Queries free/busy information for one or more calendars within a specified time range. Read search_flights Search for flights on Google Flights with full filtering and pagination. Returns structured flight data inclu Read search_hotels Search for hotels using Google Hotels via SerpAPI. Returns a list of hotels with prices, ratings, reviews, am Read search_mcp_implementations Search for MCP implementations (servers and clients) in the PulseMCP registry. This tool searches across: - I Read ssh_connection_info Get information about the configured SSH connection. Returns: JSON object with host, port, username, and auth Read ssh_download Download a file from the remote SSH server to the local machine via SFTP. Returns: Success message with trans Read ssh_list_directory List the contents of a directory on the remote SSH server via SFTP. Returns: JSON array of directory entries

EXPLORE

Related servers

Other MCP servers with similar tools — same risk classification, starter policies for each.

FAQ

Questions about Langfuse Observability

Can an AI agent delete data through the Langfuse Observability MCP server? +

Yes. The Langfuse Observability server exposes 8 destructive tools including delete_calendar_event, delete_mcp_json, delete_redirect. These permanently remove resources with no undo. PolicyLayer blocks destructive tools by default so they never reach the upstream server.

How do I prevent bulk modifications through Langfuse Observability? +

The Langfuse Observability server has 15 write tools including add_message_to_thread, add_official_mirror_to_regular_queue, add_servers_to_tenant. Set a rate limit in your policy -- for example, 10 calls per hour prevents an agent from making more than 10 modifications per hour. PolicyLayer enforces this at the gateway, before calls reach Langfuse Observability.

How many tools does the Langfuse Observability MCP server expose? +

68 tools across 4 categories: Destructive, Execute, Read, Write. 36 are read-only. 32 can modify, create, or delete data.

How do I enforce a policy on Langfuse Observability? +

Register the Langfuse Observability MCP server in PolicyLayer, apply the suggested rules above (adjust the limits to your use case), and point your AI client at the PolicyLayer proxy URL instead of the server directly. Your agents keep the same tools; PolicyLayer evaluates every call against policy before it executes. Nothing to install, live in minutes.

Enforce policy on every Langfuse Observability tool call.

Deterministic rules across all 68 Langfuse Observability tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.

ENFORCE POLICY ON LANGFUSE OBSERVABILITY →

Instant setup, no code required.

68 Langfuse Observability tools catalogued and risk-classified — across an index of 43,000+ MCP servers.