Charlotte Area Transit (CATS)

QueensCoach ♔♘

QueensCoach is an MCP server for Charlotte Area Transit System (CATS) buses and light rail, built on the agency's public GTFS schedule and GTFS-Realtime feeds. It plans trips, predicts arrivals, reads the timetable, describes routes, and reports service alerts. It runs over stdio, launched by the MCP client that uses it, or over HTTP with Google OAuth in front of it, for a hosted server. Both transports serve the same tools and resources.

Hosted server

A public instance runs on Google Cloud Run. Sign in with any Google account:

https://queenscoach.adamwanninger.com/mcp

There is zero guarantee of uptime. The hosted server is provided as-is. It may be slow, down, switched off by its spending cap, or retired without notice. For anything you rely on, run your own: over stdio, or on your own Google Cloud project with deploy/GCP.md.

Signing in tells the server your Google account's email address, which is used only to decide whether to admit you, and is never stored. The tokens it issues record your account's opaque Google ID and nothing else about you. A location you share with a tool arrives as an argument to that call, is used to answer it, and is not stored. The privacy policy and terms of service cover the hosted server.

Adding it to Claude

Claude calls a remote MCP server a connector. Custom connectors are available on Claude's paid plans.

1. Open Settings → Connectors. On the web that's claude.ai/settings/connectors; in the desktop app, Settings then Connectors.
2. Click Add custom connector at the bottom of the list.
3. Give it a name, QueensCoach, and paste the URL above as the remote MCP server URL. Leave the advanced OAuth fields empty: this server registers your client automatically.
4. Click Add, then Connect on the connector that appears. A browser window opens for the Google sign-in; approve it and it closes itself.
5. In a chat, open the tools menu and check that QueensCoach is enabled. Its seven tools then appear.

The connector belongs to your Claude account, so it follows you across web, desktop, and mobile. To disconnect, remove it from that same Connectors page; that revokes the tokens this server issued.

Adding it to Claude Code

claude mcp add --transport http queenscoach https://queenscoach.adamwanninger.com/mcp

Then run /mcp, pick queenscoach, and choose Authenticate, which opens the same Google sign-in. /mcp shows the connection's state afterwards. A server added this way loads when Claude Code next starts.

Any other client

Any MCP client that supports remote servers over streamable HTTP with OAuth works: give it the same URL and it discovers the rest.

Tools

Ask Claude "what's the closest train station to me?", "when's the next train at my stop?", or "how do I get to the airport from here?" and it passes your device's location to the tools. The server never sees a location it isn't handed, so this needs a client that shares the device's location with the model.

plan_trip

Returns up to three itineraries, each with walking and riding legs: the route, the vehicle's real destination, where to board and get off, times, the wait at each transfer, and stops travelled. Journeys with more transfers are offered only when they arrive sooner (or, for arrive_by, leave later). For trips starting within three hours of now, rides carry live delays and are marked live. walkingIsAnOption appears when the two places are within the walking limit of each other.

Walking is an estimate: the straight-line distance stretched by 30%, at 4.5 km/h. The feed has no street map, so real walks can be longer. Transfers allow up to 400 m on foot and two minutes of slack.

get_arrivals

Give either stop or a location. With a location, the filters choose the station too: mode: train finds the nearest stop a train calls at, not a closer bus stop, and the response carries its metersAway.

Returns minutes away, predicted and scheduled times, schedule deviation, the vehicle number, the platform (stopId), and that vehicle's live position. When a name query is ambiguous, the best match is used and the runners-up are listed under otherStopsMatchingQuery. Current service alerts affecting the stop or its routes are attached as serviceAlerts, in the same shape get_service_alerts returns. For times beyond the next hour or so, use get_schedule.

get_schedule

Scheduled departures with each trip's route and destination, plus firstDeparture and lastDeparture for the day. A service day runs past midnight, as GTFS does: the last trains of Tuesday leave at 1:31 am on Wednesday, and 25:30 in after or before means 1:30 am that night. Use get_arrivals for live predictions.

get_route

For each direction: the destination, the stops in order (following the pattern most trips use, with any others summarized), first and last departure, and the typical minutes between trips in the early morning, morning rush, midday, afternoon rush, evening, and late night. Also trips on each of the next seven days and the number of active alerts. A query matching several routes lists them instead.

get_service_alerts

Give at most one; with none, every alert. Ended alerts are left out. Each alert has its headline, description, effect and cause with CATS's detail text, whether it is active or upcoming, its periods (untilFurtherNotice for open-ended ones), and the routes and stops it names.

list_stops

Each station lists its stopIds, coordinates, modes, and routes (id, number, long name, mode): for example 501 · Light Rail - Lynx Blue Line, 510 · CityLYNX Gold Line, or bus routes like 29. Stops no scheduled trip calls at are left out, and nothing farther than 50 km from the location is returned.

list_vehicles

All arguments are optional; with none, every vehicle in service is returned. Each vehicle has position, heading, speed, occupancy (CATS currently reports none), headsign, and the next scheduled stop. matches and countsByMode report the total even when the list is truncated.

Resources

The feeds behind the tools, for clients and models that want the data itself.

Static tables come from the same cached download the tools use. Realtime resources are the decoded feed entities with their GTFS-Realtime field names, raw ids, and Unix timestamps, without the schedule joins the tools add. Each resource's fetchedAt is Eastern time, like the tools. stop_times.txt is large (about 12 MB in the live feed).

Install

Requires Python 3.11+.

pip install queenscoach

Or run it without installing anything, which is how most MCP clients launch it:

uvx queenscoach

From a clone instead, to hack on it or to run the HTTP transport from source:

python3 -m venv .venv

.venv/bin/pip install . # '.[gcp]' adds the Firestore token store

Transports

Pick one with --transport or QUEENSCOACH_TRANSPORT; the default is stdio.

queenscoach                                  # stdio (default)

queenscoach --transport http --port 8000 # streamable HTTP + Google OAuth

stdio

For a server the client launches itself. No authentication: the client already owns the process.

Register it with Claude Code:

claude mcp add queenscoach -- uvx queenscoach

Or in an