@pipeworx/dc-dmv
District of Columbia DMV data: service centers, the record-level vehicle inspection file,
and traffic convictions. Keyless.
Why DC gets its own pack
DC's grain is unlike any state's. The District publishes 766,879 individual vehicle
inspections keyed by VIN and 330,728 individual traffic convictions keyed by citation,
both as ArcGIS tables on the DCGIS server β not the county-level aggregates most states
publish. So the tools take VINs, violation text and date ranges rather than a county argument.
| Tool | What it returns |
|---|
dc_dmv_offices | All 9 DMV locations β service centers, the inspection station, two self-service emissions kiosks, the Deanwood road-test/CDL center, and Adjudication Services |
dc_dmv_vehicle_inspections | Inspection records by VIN or VIN prefix, with inspection and expiration dates; or inspection volume per month/year |
dc_dmv_convictions | Traffic convictions counted by violation or court disposition, or individual citation records |
Auth
None. Every upstream is a public DCGIS ArcGIS MapServer layer.
The State Plane coordinate trap
The office layer's XCOORD/YCOORD columns are Maryland State Plane metres, not lat/lng.
Georgetown Service Center reads 394380.55, 137456.23 β plausible-looking numbers that are
wrong by the width of a hemisphere if treated as coordinates.
Every query here passes geometry: true to arcgisQuery (which sets outSR=4326) and reads
latitude and longitude off the returned geometry. XCOORD/YCOORD are deliberately left
out of the response so they cannot be mistaken for coordinates downstream. Georgetown's real
position is 38.9050, -77.0648.
Gotchas worth knowing
These are live-verified behaviours, not guesses:
- The inspection file's
STATUS column is empty on all 766,879 rows, so a pass/fail
outcome is not published. What you get is that an inspection happened, when, and when the
resulting certificate expires β an expiration roughly two years out is the usual sign of a
pass, a short one of a re-inspection window. The tool's note says so rather than letting a
caller read a null as "unknown result". For per-test pass/fail with make and model,
nj_mvc_vehicle_inspections publishes it.
GIS_ID, CREATOR and CREATED are also empty on the inspection table.
- About half the conviction rows prefix the violation text with a four-digit internal code β
0201SPEED IN EXCESS OF LIMIT and SPEED IN EXCESS OF LIMIT are the same offence in two
buckets. A raw group-by therefore splits and mis-ranks every violation. The tool strips the
prefix and merges: "DISOBEYING OFFICIAL SIGN OR SIGNAL DEVICE" is 20,113 convictions, not the
10,369 a naive query reports.
- DCGIS caps any single response at 2,000 rows, grouped statistics included. Month and year
rollups group by day upstream (1,874 distinct days across the whole file β inside the cap) and
aggregate in code; if that ever hits the cap the response flags
truncated and says to narrow
with inspected_since.
- Coverage: inspections run 2020-11-01 β 2026-06-30 and are still being appended;
convictions run 2002-07-01 β 2026-06-27. Both are returned in a
coverage field rather than
assumed.
- Convictions are convictions. A citation that was dismissed or never adjudicated is absent,
so these counts are not ticket counts.
- The office layer carries no ZIP and no hours.
MATCHADDR is the District's own geocoded
street address; dmv.dc.gov posts hours per location.
Available but not wrapped
The same Transportation_DMV MapServer carries further DMV tables that are queryable but not
exposed as tools:
| Layer | Table |
|---|
| 142 | DMV Business Information |
| 143 | DMV Driver License Information |
| 144 | DMV ID Card Information |
| 145 | DMV Reciprocity Parking Permit |
| 146 | DMV Personalized Plates |
| 147 | DMV Disability Placard |
| 149 | DMV Vehicle Inspections FY2003-2013 |
| 150 | DMV Vehicle Inspections FY2014-2020 |
| 166 | DMV Boot and Tow |
Layers 149 and 150 are the historical inspection archives and share the current table's schema,
including the same empty STATUS.
Data sources
Quick Start
Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):
{
"mcpServers": {
"dc-dmv": {
"url": "https://gateway.pipeworx.io/dc-dmv/mcp"
}
}
}
Or connect to the full Pipeworx gateway for access to all 1392+ data sources:
{
"mcpServers": {
"pipeworx": {
"url": "https://gateway.pipeworx.io/mcp"
}
}
}
Using with ask_pipeworx
Instead of calling tools directly, you can ask questions in plain English:
ask_pipeworx({ question: "your question about District of Columbia DMV data" })
The gateway picks the right tool and fills the arguments automatically.
More
License
MIT