ERROR REFERENCE
Bedrock received an empty modelId
The Bedrock Runtime client rejected the InvokeModel request before inference because the required model identifier was an empty string. Fix the request value before changing IAM or model access.
WHAT IT MEANS
The request could not be serialized
operation error Bedrock Runtime: InvokeModel, serialization failed: serialization failed: input member modelId must not be empty
The SDK validates the required modelId member locally. The
call may never have reached Bedrock, so this message does not prove
that a model is unavailable or that the caller lacks permission.
NEXT CHECK
Pass the model identifier deliberately
-
Trace the value. Find the environment variable,
config file, or backend selection that supplies
modelIdand check for a missing name or empty default. - Use the exact identifier. Set a base-model ID, inference-profile ID, provisioned-model ARN, or custom-model ID supported in the target Region. Do not use a display name.
- Retry the same operation. Log only the sanitized request shape, then investigate model access or IAM only after a non-empty identifier reaches the SDK.
AUTOMATE THE TRIAGE
Keep the check in your normal workflow
SAM Doctor recognizes the exact empty-modelId serialization
marker with medium confidence and points at the request builder. Runs
locally; no AWS access, no log upload.
python -m pip install sam-doctor
sam-doctor diagnose deployment.log --format markdownRELATED
Related errors
- Bedrock model use-case details not submitted - complete the provider's first-use form in the same account and Region.
- Bedrock model identifier unresolved - compare the exact ID, Region, endpoint, and API.
- Bedrock empty system prompt - omit an empty Converse system content block before changing IAM.
OFFICIAL REFERENCE
Amazon Bedrock API
InvokeModel API reference - modelId is required for the operation.