MBTA MCP Server

by cubismod

Overview Schema Source Related Servers Discussions Admin

Python

Remote

mbta_get_stops

Retrieve MBTA stops filtered by stop ID, route, or geographic location with configurable search radius.

Instructions

Get MBTA stops. Filter by stop ID, route, or location.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "mbta_get_stops"
  }
}

Input Schema

Name	Required	Description
`stop_id`	No	Specific stop ID to get
`route_id`	No	Filter stops by route ID
`latitude`	No	Latitude for location-based search
`longitude`	No	Longitude for location-based search
`radius`	No	Search radius in meters (used with lat/lng)
`page_limit`	No	Number of results to return (default: 10)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0May 26, 2026

TDQS

C2.8/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description bears the full burden of behavioral disclosure. It only states filtering capabilities but does not mention read-only nature, pagination behavior beyond 'page_limit', or any side effects. The description adds little beyond the input schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single sentence, which is concise, but it restates the tool name ('Get MBTA stops') and does not structure information for quick parsing. It is adequate but not exemplary.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool has 6 parameters, no output schema, and many sibling tools, the description is too minimal. It does not explain return format, pagination limits (beyond default 10), or how to combine filters. The agent lacks context for effective use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Input schema has 100% description coverage for all 6 parameters, so the baseline is 3. The description paraphrases the filters ('stop ID, route, or location') but adds no new meaning beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool retrieves MBTA stops and can filter by stop ID, route, or location. However, it does not explicitly distinguish itself from sibling tools like mbta_list_all_stops or mbta_search_stops, which could cause confusion.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternative sibling tools for stops. With multiple stop-related tools, this omission makes it harder for an AI agent to select the correct one.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.