Integration Patterns

Document the query variants people actually use

This page is the operator-facing reference for Homecastr API and MCP integrations. It records practical request shapes, the fallback ladder, and the evidence behind the public guidance.

observed
observed

Directly verified from runtime-facing sources we inspected ourselves.

implemented
implemented

Verified from the current route, wrapper, or MCP handler code path.

assumed
assumed

A reasonable operational inference that still needs broader telemetry proof.

Request shape matrix

SurfaceInput shapeRouteWhat it doesEvidenceInspected source
Address lookupaddress/api/v1/forecastGeocodes first, then resolves to the forecast target used by the current product surface.observed
/api/v1/usage + route behavior audit
June 12, 2026
Parcel forecastacct/api/v1/forecast/lotUses parcel account variants and returns the latest lot-level forecast fan chart for the matched account.observed
/api/v1/usage
June 12, 2026
Unit forecastacct + include_siblings/api/v1/forecast/unitUses the same parcel key as lot-level forecasting, with optional sibling-unit expansion.observed
/api/v1/usage
June 12, 2026
Tabblock forecastgeoid/api/v1/forecast/tabblockUses a 15-digit Census GEOID20 for the highest-resolution public geography currently exposed.observed
/api/v1/usage
June 12, 2026
Tract forecastgeoid/api/v1/forecast/tractUses an 11-digit tract GEOID20 and an RPC wrapper so schema-cache changes do not break the public route.observed
/api/v1/usage + tract route code
June 12, 2026
ZCTA forecastzcta/api/v1/forecast/zctaUses a 5-digit ZIP/ZCTA area for broad coverage when tract or parcel data is unavailable.observed
/api/v1/usage
June 12, 2026
ZIP3 forecastzip3/api/v1/forecast/zip3Exposes a regional comparison geography for quick top-of-funnel market checks.implemented
MCP handler + route surface audit
June 12, 2026
County forecastfips/api/v1/forecast/countyUses a 5-digit county FIPS for market-level analysis and fallback coverage.observed
/api/v1/usage
June 12, 2026
State forecastfips/api/v1/forecast/stateUses a 2-digit state FIPS for macro comparisons across all 50 states.observed
/api/v1/usage
June 12, 2026
Legacy hexh3_id/api/v1/forecast/hexCompatibility path only. Keep for old integrations, but prefer tract or tabblock for new work.observed
/api/v1/usage + MCP handler code
June 12, 2026

Direct table access

Used where the table shape is stable enough for the public route to query the backing forecast table directly.

Route behavior audit

implemented
forecast/lotforecast/unitforecast/zctaforecast/countyforecast/state

RPC wrapper

Used where clients need schema-cache insulation or a multi-table compatibility layer.

Tract route + status route logic

implemented
forecast/tractstatus freshness checks

Legacy compatibility route

Retained for older clients and direct hex-cell integrations, but not preferred for new integrations.

/api/v1/usage + MCP handler code

observed
forecast/hexforecast_by_h3_cell

Fallback hierarchy

1. Address -> geocode

implemented

Resolve the address to a location first. If the geocode is ambiguous or missing, fail fast with a location-specific error instead of guessing.

Forecast route behavior

2. Parcel when available

observed

Prefer parcel or unit coverage when the jurisdiction supports it. That is the most specific public forecast shape today.

/api/v1/usage + product behavior review

3. Tract next

observed

If parcel coverage is absent, use tract coverage as the next stable fallback for neighborhood-level forecasting.

/api/v1/usage + product flow review

4. ZCTA, county, then state

assumed

Broaden geography only when finer coverage is unavailable. This is an inferred widening order from adjacent product flows and endpoint coverage, not a single canonical router.

Coverage surface inference

Important: the public API exposes these as separate endpoints today. This page records the current operational order, but it does not imply there is a single auto-router that walks every fallback automatically.

Status and freshness

Live-only checks

observed

Active probes against API and MCP entrypoints tell us whether a route is usable right now.

/api/v1/status + /api/v1/status/history

Freshness checks

observed

Source-specific checks based on as_of_date or similar recency metadata degrade when a source goes stale or the freshness field is missing.

/api/v1/status route logic + status history snapshots

Historical / monitoring-backed signals

observed

Persisted usage and status snapshots are the right source for trends rather than a single live request.

/api/v1/usage + /api/v1/status/history

Use the status page for live health questions. Use persisted status history and usage evidence when you need to explain whether a failure is a momentary probe issue, a transport mismatch, or a broader service problem.

API builders

Start with the most specific geography you can resolve, then widen only when coverage requires it. Prefer public routes and wrapper-backed endpoints over compatibility-only hex paths.

MCP users

Pick the tool that matches the geography you already have. Use tract or tabblock for area reasoning, parcel or unit for property reasoning, and county or state for broad comparison work.

Operators

Use the status page for live health, and use persisted usage and status history when you need evidence over time.

Evidence appendix

This appendix keeps time-bound operational examples public without mixing them into the main integration guidance. Every row below records what was inspected, when it was inspected, and what that observation does and does not prove.

ClaimLabelInspected sourceInspection dateVerification note
Observed usage window for public forecast routesobserved/api/v1/usageJune 12, 2026The inspected 30-day usage window showed all documented public forecast routes except /api/v1/forecast/zip3.
Current MCP probe exampleobserved/api/v1/status/historyJune 12, 2026The inspected snapshot recorded MCP Server as outage because the probe returned HTTP 404. That is a probe-level fact, not a durable product-health claim.
Current freshness exampleobserved/api/v1/status/history + status route logicJune 12, 2026The inspected snapshot marked the HCAD / Houston freshness check as degraded because as_of_date was stale on that source.
Wrapper and transport behaviorimplementedRepo route audit + MCP handler codeJune 12, 2026Used to verify wrapper-backed tract access, compatibility-only hex support, and MCP tool/transport exposure.

Observed limits of this audit

  • Not verified in PostHog event history for every endpoint shape.
  • Not verified in Supabase request logs for every request variant.
  • Not verified in Redis trace data for every fallback path.
  • Not verified in Vercel route logs for every deployment-time behavior.

Documentation

Reference, guide, and status pages share this navigation so the public docs set stays consistent.

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