# test_key_read_only

Test-mode keys are restricted to read operations. What causes the BioFlow API's test_key_read_only error (HTTP 403) and how to fix it.

HTTP 403 · `application/problem+json` · Test-mode keys are restricted to read operations.

## What causes it

- A `bf_test_` key was used for a write operation (POST/PATCH/DELETE). Test keys are restricted to reads by design.

## How to fix it

- Use a `bf_live_` key for writes; keep `bf_test_` keys for safe read-only integration tests.

## Example response body

```json
{
  "type": "https://getbioflow.com/docs/api/errors/test-key-read-only",
  "title": "Test-mode keys are restricted to read operations",
  "status": 403,
  "instance": "urn:request:req_01abc",
  "code": "test_key_read_only",
  "request_id": "req_01abc"
}
```

Branch on the stable `code` field — `title` and `detail` are for humans and may
change. `type` (`https://getbioflow.com/docs/api/errors/test-key-read-only`) always resolves to this page. Quote
`request_id` when contacting support. Full code registry on the
[API docs hub](/docs/api#errors); the complete surface is in the
[interactive reference](/docs/api-reference).