Docs

API reference & data

The endpoint list and coverage table below load live from the API itself, so they can't drift from what's actually deployed. If your browser can't reach api.querylines.com (or has JavaScript off), each section falls back to a direct link to the raw data.

Endpoints

Loading live from api.querylines.com/openapi.json…

Couldn't load the live spec in this browser. Read it directly: api.querylines.com/openapi.json.

Data coverage

Loading live from api.querylines.com/v1/coverage…

Couldn't load live coverage data in this browser. Read it directly: api.querylines.com/v1/coverage.

Data semantics

Source attribution

Every response, free or paid, carries a source field naming the exact publication a figure came from (for example, "FSLSO FL Monthly Premium Report, June 2026"). Facts are extracted statistics, not republished report content.

report_date and restatements

Stamping offices revise published figures (cancellations, backouts, late filings). QueryLines never overwrites a fact when that happens: a restatement creates a new row carrying the publication date it came from in report_date, and queries default to the latest report_date for each period. Pass an explicit report_date query param to pin a response to a specific historical publication instead.

data_as_of

The most recent period actually covered by the response, which can trail report_date for annual/summary endpoints that blend partial-year monthly data with a prior full-year annual report. Check data_as_of before treating a total as a complete year.

What policy_count counts

Each state's stamping office counts differently, and QueryLines serves the figure as published: FL and TX count policies, CA counts filing transactions (the SLA-CAL submitted-date series, which is also unaudited), IL counts documents filed (policies plus endorsements), and WA counts registered items. Cross-state comparisons of policy_count are apples-to-oranges; premium is directly comparable. The source field on every response names the publication behind the figure.

Carrier market share: truncated tables

The carriers dataset serves statistics derived from NAIC market share tables that are truncated at the top 10 writers per state and top 125 countrywide. Absence from a response does not mean a carrier writes no business in that state and line; paid responses restate this in a coverage_note field. Concentration is reported as CR4/CR10 (cumulative share of the top 4 and top 10 writers). HHI cannot be computed from truncated tables and is deliberately not served. Rankings mix insurance groups and standalone companies in one list, matching the report's own methodology; every row carries an entity_kind.

Building with OpenAPI-consuming tools

https://api.querylines.com/openapi.json is a standard OpenAPI 3.1 document. Custom GPTs, and any agent framework that consumes an OpenAPI spec to generate tool calls, can point at it directly. The free discovery endpoints (for example /v1/premium/sample, /v1/coverage, /v1/lines) work out of the box with no extra configuration. The paid endpoints are reachable the same way but return an x402 payment challenge instead of data until the calling tool can settle one; see Pay per query.