AWS Bedrock Error: 'ResourceNotFoundException' (Invalid Model ID)

#aws#bedrock#devops#cloud

A diagnostic guide to resolving Bedrock invocation failures caused by incorrect, deprecated, or mismatched model identifiers.

Problem

An AWS Bedrock invocation fails with an error similar to:

ResourceNotFoundException: The specified model identifier is invalid.

Typical symptoms:

• IAM permissions are correct
• Model access is enabled
• Region configuration appears valid
• Invocation fails immediately, before inference

Clarifying the Issue

This error is not an IAM failure and not a model access grant issue.

It occurs when the model ID referenced in the request does not resolve to a valid foundation model in the target region.

Common causes:

• Typo or malformed model ID
• Using a deprecated or retired model version
• Mixing model IDs across providers
• Invoking a model in a region where that specific ID does not exist

Bedrock treats model IDs as strict identifiers. If the ID does not match exactly, the resource cannot be found.

Why It Matters

This error often appears when:

• Copying model IDs from old examples or blog posts
• Upgrading model versions without updating code
• Switching between providers (Anthropic, Amazon, etc.)
• Promoting code across regions or accounts

Debugging frequently focuses on permissions, when the issue is simple identifier resolution.

Key Terms

• Model ID – Exact identifier for a Bedrock foundation model
• Model version – Specific revision of a model (often embedded in the ID)
• Provider – Model vendor (Amazon, Anthropic, Mistral, Meta)
• ResourceNotFoundException – The specific AWS error for missing or invalid resources

Steps at a Glance

1. Identify the model ID used in the request
2. Verify the model exists in Bedrock
3. Confirm the model ID matches the region
4. Check for deprecated or retired versions
5. Retest with a known-good model ID

Detailed Steps

1. Identify the Exact Model ID

Locate the model ID passed to Bedrock, for example:

• anthropic.claude-3-sonnet-20240229-v1:0
• amazon.titan-text-express-v1

Model IDs are case-sensitive and version-specific.

2. Verify the Model Exists in Bedrock

In the AWS console:

1. Go to Bedrock → Foundation models
2. Search for the model:
3. Confirm the provider
4. Confirm the full model ID
5. Confirm the model is listed at all

If the model does not appear, the ID is invalid or deprecated.

3. Confirm Region Alignment

Model existence is region-specific. Ensure:

• The console is set to the same region as your SDK or CLI
• The model appears in that region’s catalog

A valid model ID in us-east-1 may not exist in eu-west-1.

4. Check for Deprecated Versions

Older examples may reference:

• Retired preview models
• Superseded versions
• Provider-specific aliases that no longer resolve

If a newer version exists, update the model ID explicitly.

5. Retest with a Known-Good Model ID

Validate resolution directly:

aws bedrock-runtime invoke-model \
  --region us-east-1 \
  --model-id amazon.titan-text-express-v1 \
  --body '{"inputText":"Hello"}' \
  output.json

If this succeeds, the original model ID was invalid.

Pro Tips

• Model IDs are not interchangeable across providers
• Version suffixes matter — small differences break resolution
• Do not rely on blog posts for model IDs; verify in the console
• Hard-coding model IDs without validation invites drift

Conclusion

ResourceNotFoundException in AWS Bedrock is an identifier resolution failure, not a permissions or access problem.

Once:

1. The model ID is correct
2. The model exists in the target region
3. The version is current

AWS Bedrock invocation works predictably inside Amazon Web Services.

Fix the ID.
Confirm the region.
Retry the call.
Move on.

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Aaron Rose is a software engineer and technology writer at tech-reader.blog and the author of Think Like a Genius.