Functions · 3 November 2026

AWS Lambda Invoke

The AWS Lambda API on Runtime Functions now supports Invoke, so invoke in AWS's SDKs runs a function after you change only the endpoint and the keys. The payload is sent as a POST to the function's address (status.url). With InvocationType RequestResponse (the default), the call returns 200 with the function's response body. When the function returns a 4xx or 5xx status, the response also includes X-Amz-Function-Error: Unhandled. A function whose response is larger than 6 MB, whose connection closes before it responds, or that runs longer than 15 minutes also returns 200 with X-Amz-Function-Error: Unhandled, and an errorType of Function.ResponseSizeTooLarge, Runtime.ExitError or Sandbox.Timedout, so SDKs do not retry an invocation that may have run. When the function cannot accept the request, Invoke returns 429 TooManyRequestsException or 500 ServiceException. DryRun returns 204 without running the function, including for a function that has no address yet. Event is not yet supported and returns 400 InvalidParameterValueException. A function that has no address yet returns 409 ResourceConflictException. A payload larger than 6 MB returns 413 RequestTooLargeException. Concurrent invocations are limited per organization; past the limit, Invoke returns 429 TooManyRequestsException. Qualifier, LogType: Tail and ClientContext are not supported.