MBTA MCP Server

by cubismod

Overview Schema Source Related Servers Discussions Admin

Python

Remote

mbta_get_schedules

Retrieve scheduled MBTA service times with optional filters for stop, route, trip, and direction.

Instructions

Get scheduled MBTA service times.

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_schedules"
  }
}

Input Schema

Name	Required	Description
`stop_id`	No	Filter schedules by stop ID
`route_id`	No	Filter schedules by route ID
`trip_id`	No	Filter schedules by trip ID
`direction_id`	No	Filter by direction (0 or 1)
`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

C2.9/5.0

Behavior2/5

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

No annotations are present, so the description carries full burden for behavioral disclosure. It does not mention that this is a read-only operation, whether it requires authentication, or what data range it covers (e.g., current or future schedules). The description is too brief to provide transparency.

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

Conciseness4/5

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

The description is extremely concise at one sentence. It is front-loaded and efficient, but could benefit from a little more detail without becoming verbose.

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 lack of output schema and the tool having 5 optional parameters, the description should specify what the response contains or typical usage. It does not explain return format, pagination, or default behavior, making it incomplete for an agent to fully understand the tool's capabilities.

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?

Schema description coverage is 100%, meaning the input schema already documents all parameters. The description adds no additional meaning beyond what the schema provides. Baseline score of 3 is appropriate.

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 'Get scheduled MBTA service times', specifying a verb ('Get') and a resource ('scheduled MBTA service times'). However, it does not differentiate from sibling tools like mbta_get_schedules_by_time, which may cause confusion about when to use this one.

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?

No guidance is provided on when to use this tool versus alternatives. Given the presence of multiple schedule-related siblings (e.g., mbta_get_schedules_by_time), the description should indicate typical use cases or filtering scenarios.

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