> ## Documentation Index
> Fetch the complete documentation index at: https://docs.brelio.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Changelog

> What changed in the Brelio API and MCP server, and what is known not to work yet.

`/v1` only grows by addition. A breaking change ships as a new version of the operation, and the old one announces its end with `Deprecation` and `Sunset` headers.

**November 2026**

v1, early access

First release of the Brelio API and MCP server, open to clinics in early access.

**REST API** at `https://api.brelio.app/v1`:

* Team: list centers, professionals and services.
* Agenda: read the agenda, find free slots, and get, book, reschedule and cancel one-off appointments.
* Patients: search, get, create, update and archive administrative data.
* Integrations: list and revoke organization API keys and partner apps; your own keys and connections; webhooks (create, test, redeliver, rotate the secret, delete); the clinic's data policy and its decisions.
* Optimistic concurrency with `expectedVersion`, `Idempotency-Key` on every write, cursor pagination, RFC 9457 errors with stable codes, IETF `RateLimit` headers.

**MCP server** at `https://api.brelio.app/mcp`: OAuth with your Brelio account, read tools generated from the same catalogue, patient-data acceptance through URL elicitation.

**Data areas:** the clinic decides which data integrations may use; patient data is off by default and needs the clinic's and each credential's acceptance.

**Webhooks:** Standard Webhooks signatures, retries for 3 days, secret rotation with 24 hours of overlap. Event types: `webhookEndpoint.tested`.

## Known limitations

As of November 2026:

* **Personal credentials cannot use center-scoped operations.** MCP connections and personal API keys are refused the agenda, free slots, appointments and patient operations with `403 OPERATION_FORBIDDEN`, and those tools are not listed over MCP. Organization API keys and partner apps are not affected.
* **MCP is read-only.** Write tools (book, reschedule, cancel, patients, webhooks) are listed in [MCP tools](https://docs.brelio.com/en/mcp/tools.md) but not served yet; use REST.
* **Patient areas cannot be turned on in production** until the reviewed patient-data terms are published (`409 PATIENT_DATA_TERMS_PENDING`).
* **Webhooks deliver only the test event.** Appointment and patient events come next.
* **Recurring appointments** cannot be rescheduled or cancelled through the API.
* **No test mode.** There are no test credentials or test clinics yet; try the API in your own clinic with read operations first.
* **Clinical history, notes and billing** have no operations yet.


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