# QuotaLedger — US Contractor License Verification API

> Verify any US contractor license against the official state record. A free, cite-stamped, machine-readable REST API and MCP server over 299,112 normalized contractor-license records from Washington, Oregon and California. Every record carries the official source_url and an as_of date; a license that is not on file returns found:false (never a fabricated record); coverage is never overstated.

Coverage as of 2026-06-20: Washington 160,823 (full); Oregon 56,041 (full); California 82,248 (partial). Each record includes the license number, status (active / expired / suspended / other), expiry, classification and city, plus state-specific value-adds (bond and insurance currency for Oregon; contractor bond and workers'-comp for California).

Integrity guarantees: facts are copied verbatim from the official source with a source_url and as_of stamp on every record; status is a documented normalization of the official value (or, where a state publishes no status column, a transparent derivation from the official expiry — stamped in status_basis), never invented; partial coverage is flagged, never hidden; the data is offered for verification, not for sale, and answers are never editorialized.

California coverage note (verbatim): PARTIAL ingest: 82,248 records — the first slice of the CSLB Master file in file order (lowest license numbers = oldest-issued cohort). The full Master file is ~90 MB and the source streams it with no HTTP Range/resume and no gzip, so it exceeds the Engine's bounded ingest window. Re-running the SAME script in an unbounded environment completes the full ingest. Coverage is stamped honestly here and never represented as complete (integrity red line).

## REST API
- [API index](https://license-verify.pages.dev/v1): endpoints, parameters and the live coverage manifest.
- Look up a license: `GET https://license-verify.pages.dev/v1/lookup?state=CA&license=1000002` — status by state + license number; returns all endorsement rows for that license.
- Search licenses: `GET https://license-verify.pages.dev/v1/search?q=construction&state=OR&status=active` — name/keyword search with optional state and status filters.
- List by state: `GET https://license-verify.pages.dev/v1/licenses?state=WA&page=0` — paged state roster.
- Coverage + freshness: `GET https://license-verify.pages.dev/v1/states` — per-state record counts, full/partial flags, as_of dates and official source links.

## MCP server (for AI agents)
- MCP endpoint: `POST https://license-verify.pages.dev/v1/mcp` — JSON-RPC 2.0 / Streamable-HTTP, protocol 2024-11-05. Tools: lookup_license, search_licenses, list_licenses, get_coverage. An unknown license returns found:false with isError:false (an honest no-match, not an error and not a guess).
- MCP server descriptor (registry/client discovery): `GET https://license-verify.pages.dev/server.json` — modelcontextprotocol.io server.schema.json format; declares the streamable-http remote, the 4 tools, and the coverage block.

## Coverage (by state)
- [Coverage hub](https://license-verify.pages.dev/coverage/): all states, record counts and freshness.
- [Washington contractor licenses](https://license-verify.pages.dev/coverage/wa/): 160,823 licenses (full roster), 84,812 active, as of 2026-06-19. Official source: https://data.wa.gov/Labor/L-I-Contractor-License-Data-General/m8qx-ubtq.
- [Oregon contractor licenses](https://license-verify.pages.dev/coverage/or/): 56,041 licenses (full roster), 55,995 active, as of 2026-06-18. Official source: https://data.oregon.gov/d/g77e-6bhs.
- [California contractor licenses](https://license-verify.pages.dev/coverage/ca/): 82,248 licenses (partial coverage, flagged), 77,963 active, as of 2026-06-18. Official source: CA CSLB — Master List of California Licensed Contractors (License Master).

## Professions (by trade)
- [Professions hub](https://license-verify.pages.dev/professions/): cross-state trade overviews.
- [General Contractors](https://license-verify.pages.dev/professions/general-contractor/): 180,364 licenses across CA, OR, WA.
- [Electrical Contractors](https://license-verify.pages.dev/professions/electrical/): 15,778 licenses across CA, WA.
- [Plumbing Contractors](https://license-verify.pages.dev/professions/plumbing/): 7,297 licenses across CA, WA.
- [Painting Contractors](https://license-verify.pages.dev/professions/painting/): 10,128 licenses across CA, WA.
- [Landscaping Contractors](https://license-verify.pages.dev/professions/landscaping/): 6,350 licenses across CA, WA.

## About
- [Home and docs](https://license-verify.pages.dev/): value proposition, a live verification search box and transparent pricing (a free Stage-0 probe; pay-per-use planned, nothing charged today).
- [Sitemap](https://license-verify.pages.dev/sitemap.xml): all canonical URLs.
- Disclaimer: an independent aggregator of official records, not the authoritative registry of record; for legal certainty consult the issuing state board directly.