Errors and rate limits | HollrAI

Error shape

API errors use the following structure:

1 {
2   "status": "error",
3   "error_code": "400",
4   "message": "Missing campaign_id"
5 }

error_code is the HTTP status code represented as a string. message contains a human-readable explanation intended for debugging and logs.

Status	Meaning
`400`	The request is missing a required field or contains invalid input.
`401`	The `hollr-api-key` header is missing or the key is not recognized.
`403`	The key is valid but is not authorized for the requested resource.
`404`	The requested campaign or conversation was not found or is not accessible to the account.
`429`	A request or concurrency limit has been exceeded.
`500`	An unexpected error occurred on HollrAI’s side.

The current API contract documents two limits:

60 requests / minute

Applies per API key across the API.

5 concurrent calls

Applies per API key to POST /v1/call/make-call. The bulk endpoint does not enforce this specific concurrency limit.

A 429 response uses the standard error shape.

1 {
2   "status": "error",
3   "error_code": "429",
4   "message": "Too many requests. Please wait before trying again."
5 }

If you need to trigger many calls, prefer /v1/call/bulk-calls rather than issuing many individual make-call requests in parallel.