---
title: "Dependency health check"
method: GET
path: "/v1/health/deep"
tags: ["Health"]
---

# Dependency health check

`GET /v1/health/deep`

## Request

- Base URL: `https://api.registrum.co.uk`
- URL: `https://api.registrum.co.uk/v1/health/deep`
- Auth: none required

Check that all upstream dependencies are reachable.

Tests connectivity to the Companies House API and Supabase database,
and reports per-dependency status and response times. No authentication required.

Also reports **`api_self_check`** - not an upstream, but this API's own
self-check probe: whether it is still running here, and what it last saw
when it called `GET /v1/company/{n}` through the public hostname. An
external uptime monitor watching this endpoint for the word `unhealthy`
therefore also catches the case where our internal monitoring has stopped.

- **healthy** - all dependencies responding normally
- **degraded** - one or more dependencies are slow or unreachable (the API will still serve cached data)

**Upstream usage:** 1 upstream call to the Companies House API (a lightweight search probe).
Do not poll this endpoint at high frequency - once per minute is sufficient for monitoring.

## Response `200`

Successful Response

- DeepHealthResponse: Checks all upstream dependencies (Companies House API, Supabase) and reports their status.
  - `status` string: Overall status: 'healthy' if all deps are up, 'degraded' if any are down
  - `uptime_seconds` number: Seconds since the server started
  - `version` string: API version number
  - `dependencies` DependencyHealth[]: Per-dependency health status
    - `name` string, required: Dependency name (e.g., 'companies_house_api', 'supabase')
    - `status` string, required: 'healthy', 'unhealthy', or 'degraded'
    - `response_time_ms` number, nullable: Response time in milliseconds
    - `error` string, nullable: Error message if unhealthy

---

[API](https://skmtc.dev/registrum/apis/registrum-api.md) · [All operations](https://skmtc.dev/registrum/apis/registrum-api/llms.txt) · [OpenAPI document](https://skmtc.dev/registrum/apis/registrum-api/revisions/2bf0ecf7cc02?raw)