@pipeworx/wa-dmv

Washington State DMV MCP — the Department of Licensing's VIN-level electric-vehicle population and its monthly vehicle-registration transaction counts. Keyless.

Washington has no agency called "the DMV": vehicle registration and driver licensing are run by the Department of Licensing (DOL). Both names appear in the tool descriptions because agents search for "WA DMV".

Tools

Related MCP server: mcp-data-wa

Auth

Keyless. Both datasets are public Socrata resources on data.wa.gov; no app token is required at the volumes this pack issues.

Per-state gotchas

• hmzg-s6q4 counts transactions, not vehicles. This is the trap in this state. King County processes roughly 160,000 registration transactions a month, so summing every month back to fiscal 2017 returns 17.6M for one county — arithmetically correct and completely misleading. wa_dmv_registration_transactions therefore pins every query to one fiscal year (the latest by default) or one calendar month, and labels the result "registration transactions during <period>". For the size of a registered fleet, use wa_dmv_ev_population.

• Washington fiscal years run July 1 – June 30. Fiscal 2026 covers July 2025 through June 2026. Data starts at fiscal 2017.

• The month column stores the last day of the month. Filter it with date_trunc_ym, which the month argument (YYYY-MM) does for you; results are reported back as YYYY-MM.

• Case differs by column. Counties and cities are plain mixed case (King, Seattle); makes and models are upper case (TESLA, MODEL 3).

• Roughly two-thirds of EV rows carry electric_range 0. 188,456 of 289,564 vehicles sit in the "Eligibility unknown as battery range has not been researched" CAFV bucket with a literal zero range, which drags any average down. The genuinely researched vehicles average ~133 miles. Treat average_electric_range_miles as a floor, not a spec.

• Socrata reports an all-zero average as the string "0E-24". The shared govNumber helper strips exponent notation into NaN, so this pack parses averages with its own avgMiles.

• ev_type has exactly two values, spelled in full: Battery Electric Vehicle (BEV) and Plug-in Hybrid Electric Vehicle (PHEV). The ev_type argument accepts BEV / PHEV / plain phrases.

• sum_of_returned_rows is not a total. Row lists are cut off by limit; total_electric_vehicles and total_transactions_in_period are separate full counts over the same filters and are the figures to quote.

Data sources

• EV population — https://data.wa.gov/resource/f6w7-q2d2.json (Electric Vehicle Population Data)

• Registration transactions — https://data.wa.gov/resource/hmzg-s6q4.json (Vehicle Registration Transactions by County)

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "wa-dmv": {
      "url": "https://gateway.pipeworx.io/wa-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 Washington DMV (Dept of Licensing) data" })

The gateway picks the right tool and fills the arguments automatically.

More

• All tools and guides

• pipeworx.io

License

MIT