Amazon Bedrock (Runtime API) error
Amazon Bedrock 400 ValidationException: what it means and how to fix it
400 ValidationExceptionRetry? NoLast verified 2 documented fixes3 sources
What it means
The input fails to satisfy the constraints specified by Amazon Bedrock. The troubleshooting guide documents this as ValidationError.
Causes
- Missing or incorrectly formatted required parameters
- Input values outside the allowed ranges or not matching expected patterns
How to fix it
- Fix 1.
Review the API documentation to ensure all required parameters are included and formatted correctly.
- Fix 2.
Check that your input values are within the allowed ranges or conform to the expected patterns, and follow the validation rules in the API reference for the action you are using.
More Amazon Bedrock errors
All 22 Amazon Bedrock errorsHTTP 400 at other providers
Compare 400 across providers400 invalid_request_errorRetry? Not statedAnthropic API400 invalid_request_error (spend limit reached)Retry? Not statedAnthropic API400 Bad RequestRetry? Not statedAzure OpenAI400 content_filterRetry? Not statedAzure OpenAI400 Bad RequestRetry? Not statedCohere API400 Bad Request (too many tokens)Retry? Not statedCohere API400 - Invalid FormatRetry? Not statedDeepSeek API400 invalid_requestRetry? NoGemini API400 failed_preconditionRetry? NoGemini API400 parameter_unknownRetry? NoGemini API400 INVALID_ARGUMENTRetry? NoGemini API400 FAILED_PRECONDITIONRetry? NoGemini API
FAQ
What does the Amazon Bedrock error "400 ValidationException" mean?
The input fails to satisfy the constraints specified by Amazon Bedrock. The troubleshooting guide documents this as ValidationError.
How do I fix Amazon Bedrock "400 ValidationException"?
There are 2 documented fixes. Start with the first: Review the API documentation to ensure all required parameters are included and formatted correctly.
Should I retry Amazon Bedrock "400 ValidationException"?
No. The official docs treat this error as not retryable: fix the cause before sending the request again.
Which other AI APIs return HTTP 400?
Per their official error docs: Anthropic API (400 invalid_request_error; 400 invalid_request_error (spend limit reached)), Azure OpenAI (400 Bad Request; 400 content_filter), Cohere API (400 Bad Request; 400 Bad Request (too many tokens)), DeepSeek API (400 - Invalid Format), Gemini API (400 invalid_request; 400 failed_precondition; 400 parameter_unknown; 400 INVALID_ARGUMENT; 400 FAILED_PRECONDITION), Groq API (400 Bad Request), Mistral API (400 Bad request), OpenAI API (400 invalid_request_error (Invalid service_tier argument); 400 BadRequestError), OpenRouter (400 invalid_request; 400 invalid_prompt; 400 context_length_exceeded; 400 max_tokens_exceeded; 400 token_limit_exceeded; 400 string_too_long; 400 invalid_image; 400 image_too_large; 400 image_too_small; 400 unsupported_image_format; 400 image_download_failed), Vertex AI (400 INVALID_ARGUMENT / FAILED_PRECONDITION), xAI API (400 Bad Request).
Sources
Last verified against 3 sources: Amazon Bedrock's official docs and official SDK repositories.
- docs.aws.amazon.comhttps://docs.aws.amazon.com/bedrock/latest/APIReference/API_runtime_InvokeModel.html
- docs.aws.amazon.comhttps://docs.aws.amazon.com/bedrock/latest/userguide/troubleshooting-api-error-codes.html
- docs.aws.amazon.comhttps://docs.aws.amazon.com/sdkref/latest/guide/feature-retry-behavior.html
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