---
title: "Changelog"
description: "Dated changes to the Tendral Health API."
url: https://developer.tendralhealth.com/changelog
---

# Changelog

## 2026-10-07 · API: Every error uses the error envelope

A failure on our side now answers `500` with code [`INTERNAL_ERROR`](/docs/errors#INTERNAL_ERROR) in the standard envelope, with `request_id` and `doc_url`; before, it answered a shorter body. A `cursor` the API did not return, and a `limit` outside 1–500, now answer `400` [`INVALID_PARAMETER`](/docs/errors#INVALID_PARAMETER); before, the list silently restarted at the first page or the limit was capped at 500. Successful responses are unchanged.

## 2026-10-07 · Docs: New developer docs

New pages for environments, versioning and release phases, and security. Every page has a Markdown copy, and llms.txt links to them. The Surveys API endpoints, which were never callable, moved out of the API reference to an [Early access](/docs/early-access/surveys-api) page.

## 2026-05-06 · API: API v1

Version 1 of the API: bearer keys with scopes, the error envelope with `doc_url` and `request_id`, per-key rate limits with `X-RateLimit-*` headers, `Idempotency-Key` on writes, and cursor pagination.