Developers

REST API and MCP connector

Every response carries the same envelope the UI reads: data, plus sources, assumptions, gaps, confidence, warnings, engine versions and disclaimers.

Response envelope

{
  "data": { ... },
  "meta": {
    "generatedAt": "2026-07-26T12:00:00.000Z",
    "engineVersions": { "zoning": "1.2.0", "envelope": "1.3.0", ... },
    "confidence": "medium",
    "sources": [ { "sourceName": "...", "citation": { "section": "..." }, "effectiveDate": "...", "retrievedAt": "..." } ],
    "assumptions": [ { "label": "...", "value": 11, "origin": "platform_default", "rationale": "..." } ],
    "gaps": [ { "label": "...", "reason": "...", "remediation": "..." } ],
    "warnings": [ "..." ],
    "disclaimers": [ "..." ]
  }
}

Endpoints

Method	Path	Purpose
POST	/api/v1/addresses/search	Resolve an address or APN to ranked parcel candidates
GET	/api/v1/parcels/{id}	Parcel record, geometry, ownership, tax, improvements, easements
GET	/api/v1/parcels/{id}/zoning	Base district, overlays, dimensional standards, use table
GET	/api/v1/parcels/{id}/envelope	Buildable envelope geometry, area and lot-line classification
GET	/api/v1/parcels/{id}/yield	Footprint, floor area, stories, units by use, parking, subdivision
GET	/api/v1/parcels/{id}/plans	Architectural plan matches with placement geometry
GET	/api/v1/parcels/{id}/comparables	Comparable sales grid with every adjustment
GET	/api/v1/parcels/{id}/valuation	Reconciled valuation with approach weights
GET	/api/v1/parcels/{id}/scenarios	Available scenario templates for the parcel
POST	/api/v1/parcels/{id}/scenarios	Run a scenario with overrides and receive the full pro forma
POST	/api/v1/copilot/ask	Ask the Copilot; returns the answer, tool transcript and guardrail verdict
GET	/api/v1/jurisdictions	Published jurisdictions, rules versions and known gaps
GET	/api/v1/sources	Source registry with licence and acquisition method
GET	/api/v1/me	Current identity, organisation, plan, entitlements and quota status
GET	/api/v1/openapi.json	Machine-readable specification

Standards

Versioned path prefix; no breaking change without a new version
Bearer API key or session authentication; scopes per key
Rate limited per organisation, with limit headers on every response
Idempotency keys on writes
Every access written to the audit log
Errors return a machine-readable code, a human message, and the remedy

MCP connector

Groundline ships a Model Context Protocol server so an AI assistant can use the same tools the Copilot uses — with the same guardrails. Run npm run mcp for the stdio server.