Check current conditions along a major California highway corridor.

The flagship trip-check tool: give it a start and end place and it returns everything active along that stretch right now - CHP incidents, lane closures physically in place, chain controls, and wildfires within ~10 miles - ordered by miles from the start, plus a summary.

ALWAYS pass from_coords and to_coords ("lat,lon") when you know where the places are - for landmarks, small towns, or anything not a major city they are required for a good answer. Coordinates do two things: they let unlisted places resolve to the nearest corridor (e.g. "Alice's Restaurant" snaps to I-280 on the Peninsula), and they CLIP the route to the span actually being driven, so a trip to a mid-corridor destination doesn't report events beyond it.

Corridors covered: I-80 Sacramento-Reno, US-50 to South Lake Tahoe, I-5, US-101, SR-17, SR-99, SR-1, I-15 to Vegas, Bay Area freeways, Tahoe-area routes. This is NOT a general router: if nothing matches (even with coordinates), the response lists the covered corridors; fall back to the filtered tools with center= for anything else.

Freshness: CHP incidents refresh about once a minute; closures, chain controls, and fires are on a 5-minute cache. Current conditions only - this cannot forecast tomorrow's weather or closures.

Full current-conditions report for a California region.

Use this for area-scale questions ("how is the Bay Area?", "what's happening in SoCal?") instead of stitching together point queries. It sweeps every source over the whole region at once: CHP incidents (severity-sorted, worst first), lane closures in place (full closures called out), chain controls, and wildfires inside the region.

Regions: Bay Area, Sacramento metro, Tahoe/Sierra, Central Valley, Southern California, San Diego, Central Coast, North State. An unrecognized region name returns the list.

Large regions are capped to the most severe items; the counts are always exact and the response says when a list was truncated. Freshness: CHP ~1/min fetched live, everything else 5-minute cache.

Live CHP traffic incidents statewide, optionally filtered.

Data: the California Highway Patrol statewide computer-aided dispatch feed - collisions, traffic hazards, disabled vehicles, closures as CHP logs them. Refreshes about once a minute; incidents disappear when CHP closes the log. Fetched live on every call.

Filters (combinable):

• highway: a route like "I-80", "US 50", "17", "Hwy 99". Matches incidents whose location text mentions that route.

• center: "lat,lon" with radius_km - incidents within that circle. THIS IS THE RIGHT FILTER FOR A TOWN OR PLACE NAME: use your knowledge of where the place is (e.g. Coyote, CA -> "37.22,-121.74") with radius_km 15-30. A circle catches every road around the place, not just one highway.

• area: substring match on the CHP dispatch-area name. These are CHP communication-center names ("Hollister Gilroy", "East Sac", "Golden Gate"), NOT town names - do not pass a town here. There is no county filter because CHP's feed carries no county field; for a county, use center on the county seat with a radius covering the county.

Limits: locations are free-text from dispatchers; a few incidents lack usable coordinates and are omitted. No history - current logs only.

Caltrans lane and road closures physically in place RIGHT NOW.

Data: the Caltrans Lane Closure System (LCS). Only closures that crews have actually established (CHP code 1097) and not yet picked up are returned - scheduled-but-not-started closures are excluded, so this is "what is blocking lanes now", not a construction calendar. Refresh: 5-minute cache over per-district Caltrans feeds.

Filters: route (e.g. "I-80", "US 101", "1"); district (Caltrans district 1-12, e.g. 3 = Sacramento/Tahoe, 4 = Bay Area, 7 = Los Angeles); center "lat,lon" with radius_km - closures whose begin or end point is inside the circle. For a town or place, center is the filter that catches work on EVERY road around it, including small state routes.

Read closure_class on each record, it is what the closure means for through traffic:

• "full-roadway": the road itself is closed in that direction. The only class that means "you can't drive through".

• "ramp": a ramp or connector is closed (even when the raw record says "Full", that means the ramp is fully closed, not the highway).

• "one-way-traffic": alternating single lane with flagging; passable with delays. Common on two-lane mountain roads.

• "alternating-lanes", "moving", "traffic-break": rolling or brief work; minor delays.

• "lane": some lanes closed; the lanes field says how many of how many. estimated_delay_minutes is present when crews reported one. Shoulder-only work is excluded entirely.

Current chain-control requirements on California mountain highways.

Data: Caltrans chain-control status for fixed checkpoints on mountain routes (I-80 Donner, US-50 Echo Summit, SR-88, SR-89, and others). Levels: R-1 = chains OR snow tires required; R-2 = chains required except 4WD/AWD with snow tires on all four; R-3 = chains on ALL vehicles (rare, usually precedes closure). Refresh: 5-minute cache.

Filters: route (e.g. "80", "US-50", "SR-88"); center "lat,lon" with radius_km for all checkpoints around a place (e.g. around Truckee), whatever highway they are on.

Off-season (roughly May-October) there are usually no controls anywhere; the response says so explicitly rather than returning an empty list. Chain requirements can change hour to hour in storms - tell the user the data_as_of time and to carry chains anyway when snow is possible.

Active California wildfires, flagged when close to a major highway.

Data: the interagency WFIGS current-wildfire feed (NIFC) - name, size in acres, percent contained, discovery date. Points are each fire's ORIGIN, not its perimeter: a large fire can affect roads far from this point. Refresh: 5-minute cache; size/containment typically update once or twice a day. Small, fast-moving local fires may appear in CHP incident logs (get_incidents, type "FIRE-Report of Fire") before this feed has them.

Filters:

• near_route (e.g. "I-5", "101") - only fires within ~10 miles of that highway's corridor line.

• center "lat,lon" with radius_km - fires around a place, regardless of highway. Without either, every active CA fire is returned, each carrying a near_highways list of major corridors within ~10 miles (empty = not near a covered major highway; it may still affect local roads).

This tool does NOT know about road closures caused by fires - cross-check get_incidents and get_lane_closures for the affected area.

Which major corridors have the most going on right now.

Answers broad questions like "what are the busiest routes", "where is traffic worst", or "which highways should I avoid today" across all 17 tracked corridors. by="activity" ranks on live events (full closures weigh most, then incidents, lane closures, chain controls); by="congestion" ranks on measured speed vs free-flow at each corridor's midpoint and needs the traffic feed to be configured - if it is not, the ranking silently falls back to activity.

Each entry carries the counts and a one-line reason, so the answer can say WHY a corridor ranks where it does, not just list names.

Live Caltrans roadside camera snapshots near a point or on a route.

Data: ~3,000 in-service Caltrans cameras statewide. Every returned image_url was verified live moments ago (offline cameras that serve a placeholder frame are filtered out), so images can be shown directly. Snapshots refresh roughly every minute; stream_url (when present) is an HLS video stream.

Filters: center "lat,lon" (required unless route is given) with radius_km; route (e.g. "I-80", "50") narrows to that highway. Results sort nearest-first when a center is given. Use a camera to let the user SEE conditions: fog on the pass, snow on the pavement, traffic density at an interchange.

What Caltrans changeable message signs are displaying right now.

Data: statewide CMS sign text, blank and out-of-service signs already filtered - every record is a message a driver is physically seeing. Signs carry the road's operational truth ("CHAINS REQUIRED 10 MI AHEAD", "FULL CLOSURE HWY 96 DUE TO FIRE", "PREPARE TO STOP"), often before the event shows up in any other feed. Refresh: ~2-minute cache.

Filters: route (e.g. "I-80") and/or center "lat,lon" with radius_km. Quote sign text verbatim to the user - it is the most current and most local signal this server has.

Live road events near a point anywhere CommuteScout covers, not just California: 37 states today, growing.

Data: the same multi-state feeds the live map shows, normalized - state DOT incidents, roadwork and closures, chain and traction advisories, and nationwide wildfires. Every event names its publishing agency in the source field. Coverage varies by state (some publish roadwork only; docs/state-coverage.md has the matrix); states added later appear here automatically.

For CALIFORNIA questions prefer the dedicated tools above (richer detail: dispatch logs, lane counts, chain levels). Use THIS tool for any location outside California, near a state border, or as a supplement when a California tool comes back empty.

center is "lat,lon". kinds is a comma list from: incident, closure, chain, fire, sign, rwis, camera, toll (toll adds live and fixed toll prices where agencies publish them). radius_km caps at 160.