Real-time Chicago transit data for your OpenClaw agent. Get L train arrivals, bus predictions, service alerts, and route info for all CTA services.
For anyone who rides CTA and wants:
- Real-time L train arrivals — know exactly when the next train comes
- Bus predictions — see when your bus will arrive at your stop
- Live vehicle tracking — see where trains and buses are right now
- Service alerts — know about delays, detours, and disruptions before you leave
- Stop and route lookup — find the nearest stop or explore a route's path
How it works: Data comes from CTA's three official APIs — Train Tracker, Bus Tracker, and Customer Alerts. Train and bus data require free API keys. Alerts always work with no key.
- Train Tracker key: Apply at https://www.transitchicago.com/developers/traintrackerapply/
- Bus Tracker key: Apply at https://www.transitchicago.com/developers/bustracker/
cp .env.example .env
# Then edit .env and add your keys:
# CTA_TRAIN_API_KEY=your-train-key-here
# CTA_BUS_API_KEY=your-bus-key-here# Copy to your skills directory
cp -r cta-skill ~/.openclaw/skills/cta
# Or for a workspace-specific install:
cp -r cta-skill <workspace>/skills/cta# One-time download of routes, stops, and schedules
node scripts/cta.mjs refresh-gtfsNote: Re-run refresh-gtfs periodically when CTA updates their schedule. Alert commands work even without API keys or GTFS data.
- See when the next L train arrives at any station
- Search stations by name — no need to memorize IDs
- Filter by L line (Red, Blue, Brown, etc.)
- Shows "Due" for approaching trains, minutes for upcoming
- Real-time bus arrival predictions at any stop
- Filter by route number
- Search for stops by name
- View live positions of all active trains on a line
- View live positions of all active buses on a route
- Positions update every 30-60 seconds
- Active delays, detours, and service disruptions
- Filter by route — works for both L lines and bus routes
- No API key required — alerts always work
- Search for stops by name or proximity to a location
- List all CTA routes (L lines + 129 bus routes)
- View every stop along a route in order
Just ask your agent naturally:
- "When's the next Red Line at Belmont?"
- "Is the Blue Line running to O'Hare?"
- "Any CTA service alerts right now?"
- "Where are the Brown Line trains?"
- "When does the 22 bus come to Clark & Diversey?"
- "Find CTA stops near Wrigley Field"
- "What bus routes does CTA run?"
# Search by station name
node scripts/cta.mjs arrivals --stop-search "belmont" --route Red
# Or use the exact station ID
node scripts/cta.mjs arrivals --mapid 41320
# Or search by station name
node scripts/cta.mjs arrivals --station "Clark/Lake"# When does the 22 bus arrive at my stop?
node scripts/cta.mjs bus-arrivals --stop 1836 --route 22
# Where are all the 77 Belmont buses?
node scripts/cta.mjs bus-vehicles --route 77# What stops are within 0.3 miles of the Loop?
node scripts/cta.mjs stops --near 41.8781,-87.6298 --radius 0.3# All current alerts
node scripts/cta.mjs alerts
# Just Red Line alerts
node scripts/cta.mjs alerts --route Red| What You Want | Command |
|---|---|
| Train Arrivals | |
| Search station by name | cta.mjs arrivals --stop-search "ohare" |
| Arrivals at station | cta.mjs arrivals --station "Clark/Lake" |
| Arrivals by station ID | cta.mjs arrivals --mapid 40380 |
| Arrivals by stop ID | cta.mjs arrivals --stop 30070 |
| Filter by L line | cta.mjs arrivals --stop-search "belmont" --route Red |
| Bus Predictions | |
| Bus arrivals at stop | cta.mjs bus-arrivals --stop 456 |
| Filter by route | cta.mjs bus-arrivals --stop 456 --route 22 |
| Search bus stop | cta.mjs bus-arrivals --stop-search "michigan" |
| Vehicle Tracking | |
| Train positions on a line | cta.mjs vehicles --route Red |
| Bus positions on a route | cta.mjs bus-vehicles --route 22 |
| Alerts | |
| All service alerts | cta.mjs alerts |
| Alerts for a route | cta.mjs alerts --route Red |
| Stops | |
| Search by name | cta.mjs stops --search "belmont" |
| Find nearby stops | cta.mjs stops --near LAT,LON |
| Set search radius | cta.mjs stops --near LAT,LON --radius 0.5 |
| Routes | |
| All routes (L + bus) | cta.mjs routes |
| All bus routes (live API) | cta.mjs bus-routes |
| Route details + stops | cta.mjs route-info --route Red |
| Bus route stops | cta.mjs route-info --route 22 |
| Maintenance | |
| Refresh GTFS data | cta.mjs refresh-gtfs |
| Code | Line | Terminals |
|---|---|---|
| Red | Red Line | Howard ↔ 95th/Dan Ryan |
| Blue | Blue Line | O'Hare ↔ Forest Park |
| Brn | Brown Line | Kimball ↔ Loop |
| G | Green Line | Harlem/Lake ↔ Ashland/63rd or Cottage Grove |
| Org | Orange Line | Midway ↔ Loop |
| P | Purple Line | Linden ↔ Howard (Express to Loop weekdays) |
| Pink | Pink Line | 54th/Cermak ↔ Loop |
| Y | Yellow Line | Dempster-Skokie ↔ Howard |
| Route | Name | Notes |
|---|---|---|
| 22 | Clark | Major north-south corridor |
| 36 | Broadway | North Side lakefront |
| 77 | Belmont | Major east-west crosstown |
| 151 | Sheridan | Lakefront express |
| 146 | Inner Drive/Michigan Express | Loop to north lakefront |
| 8 | Halsted | Long north-south route |
| 9 | Ashland | Major north-south corridor |
| 49 | Western | Longest route in system |
| 66 | Chicago | Major east-west route |
| 79 | 79th | Major south side east-west |
Once published on ClawHub, users can install this skill with:
clawhub install ctaManual installation:
cp -r cta-skill ~/.openclaw/skills/cta
cd ~/.openclaw/skills/cta && npm install
node scripts/cta.mjs refresh-gtfs| Requirement | Details | How to Get |
|---|---|---|
| Node.js 18+ | Runtime for the skill | nodejs.org |
| unzip | Required for GTFS data extraction | Pre-installed on most systems |
| CTA Train API Key | Required for train commands | Apply here |
| CTA Bus API Key | Required for bus commands | Apply here |
Note: Alert commands (alerts) work without any API keys.
| API | Auth | Update Frequency |
|---|---|---|
| Train Tracker | API key (free) | ~1 minute |
| Bus Tracker v2 | API key (free) | ~30 seconds |
| Customer Alerts | None (open) | As needed |
| GTFS Static | None (open) | Periodic schedule updates |
Solution: Get a free key and add it to your .env file:
# Apply at: https://www.transitchicago.com/developers/traintrackerapply/
CTA_TRAIN_API_KEY=your-key-hereSolution: Get a free key and add it to your .env file:
# Apply at: https://www.transitchicago.com/developers/bustracker/
CTA_BUS_API_KEY=your-key-herePossible causes:
- Key was copy-pasted incorrectly (check for extra spaces)
- Key hasn't been activated yet (can take a few minutes after signup)
- Daily request limit exceeded (50,000/day for train; similar for bus)
Possible causes:
- No active service at this time (late night, holidays)
- Station/stop ID is incorrect — try
--stop-searchto find the right one - API may be temporarily unavailable
Solution: Run the one-time data download:
node scripts/cta.mjs refresh-gtfsThis is expected if API keys aren't set. Alerts use the Customer Alerts API which requires no authentication. Set CTA_TRAIN_API_KEY and CTA_BUS_API_KEY for full functionality.
| Fare Type | Price |
|---|---|
| Regular (Ventra/contactless) | $2.50 |
| Bus transfer | $0.25 |
| Rail-to-rail transfer | Free within 2 hours |
| Reduced fare | $1.25 |
| 1-Day Pass | $5.00 |
| 3-Day Pass | $15.00 |
| 7-Day Pass | $20.00 |
| 30-Day Pass | $75.00 |
- CTA Developer Center — Official API docs and key signup
- Train Tracker API Docs — Detailed train API reference
- Bus Tracker API Docs — Detailed bus API reference
- CTA System Map — Official route maps
- GTFS Reference — The data format standard used by transit agencies worldwide
Skill Type: Data Integration (CTA REST APIs + GTFS) Runtime: Node.js Created for: ClawHub / OpenClaw License: MIT
Credits:
- Transit data provided by Chicago Transit Authority (CTA)
- Train Tracker, Bus Tracker, and Customer Alerts APIs by CTA
- GTFS static data published by CTA
Ready to ride? Get your free API keys, set them up, and never miss your train again.