# BuzzerAPI

- [Hosted MCP connector (development)](https://www.buzzerapi.com/mcp.md): OAuth linking, building-specific tools, safety and client installation. Not released or directory-approved yet.

> Phone-based apartment and condo buzzer access for AI agents and applications. Works with call boxes that dial a phone number. Account creation, up to 3 active AI agent keys without a paid subscription (20 with one), and up to 20 stored access rules per building are free to set up; rules open the door only after a subscription, a provisioned number, and an entrance test.

- [OpenAPI 3.1 contract](https://www.buzzerapi.com/openapi.json): machine-readable public /v1 contract. Also reachable at `GET https://api.buzzerapi.com/v1/openapi.json` (302 redirect) and as `openapi_url` in `GET /v1/health`.

- [AI agent onboarding](https://www.buzzerapi.com/agents.md): discovery terms, setup, hosted subscription checkout, API key, and access rules.
- [Pricing and free signup](https://www.buzzerapi.com/#pricing): verify email, copy a scoped API key and AI agent setup prompt, then subscribe when ready for a number. BuzzerAPI is $4 per week or $104 per year ($2 per week billed annually).
- [Account setup](https://www.buzzerapi.com/app.html): create AI agent keys, see and revoke every key and website sign-in, manage webhook endpoints, and manage hosted checkout, subscription status, and building setup.
- [Property manager email](https://www.buzzerapi.com/agents.md#ask-the-property-manager-to-connect-the-call-box): the drafted email an AI agent should give the owner to ask their property manager to have the call box dial the virtual number.

Multiple buildings: each building uses one unit at the same BuzzerAPI subscription price and receives its own virtual number. Parent-account AI agents can list buildings with `GET /v1/buildings`, name one in the path of every building request (such as `/v1/buildings/{buildingId}/unlock`), and use building preview and execute endpoints to add or remove buildings in the United States or Canada. Poll `GET /v1/buildings/{buildingId}/logs` or register a webhook (`POST /v1/webhooks`, HMAC-SHA256 signed; creation, testing and delivery require an active paid subscription, excluding trials) to follow access activity. Timers and passcodes take `remaining_uses` (for example `"remaining_uses":1` for a single delivery), and access creation requires an `Idempotency-Key`. Retry with the original key and identical body; deleting a rule frees its key.

- [Complete documentation](https://www.buzzerapi.com/docs.html): sign-in, subscriptions, keys, building lifecycle, access, logs, webhooks, and REST endpoints.

- [Full REST reference](https://www.buzzerapi.com/api-reference): all endpoints, schemas, permissions, limits, and recovery.
- [Webhooks and signature verification](https://www.buzzerapi.com/docs#webhooks): account-level endpoints (`GET`, `POST /v1/webhooks`, `DELETE /v1/webhooks/{id}`, `POST /v1/webhooks/{id}/test`), events, retries, and Node and Python verification. Queued deliveries are cancelled when an active paid subscription is absent; listing and deleting endpoints remain available. Deduplicate on event `id`; delivery order is not guaranteed, so order by `data.occurred_at`.