AIF-C01 Applications of Foundation Models Practice Question

Exhibit

Resources:
  BedrockAgent:
    Type: AWS::Bedrock::Agent
    Properties:
      AgentName: MyAgent
      FoundationModel: anthropic.claude-v2
      Instruction: "You are a helpful assistant."
      KnowledgeBases:
        - KnowledgeBaseId: !Ref MyKnowledgeBase
      PromptOverrideConfiguration: null
  MyKnowledgeBase:
    Type: AWS::Bedrock::KnowledgeBase
    Properties:
      Name: MyKB
      RoleArn: !GetAtt KBRole.Arn
      KnowledgeBaseConfiguration:
        Type: VECTOR
        VectorKnowledgeBaseConfiguration:
          EmbeddingModelArn: !Sub arn:aws:bedrock:${AWS::Region}::foundation-model/amazon.titan-embed-text-v1
      StorageConfiguration:
        Type: OPENSEARCH_SERVERLESS
        OpensearchServerlessConfiguration:
          CollectionArn: !GetAtt MyCollection.Arn
          VectorIndexName: my-index
  MyCollection:
    Type: AWS::OpenSearchServerless::Collection
    Properties:
      Name: my-collection
      Type: VECTORSEARCH

Refer to the exhibit. A developer deploys this CloudFormation stack but the agent fails to query the knowledge base. What is a likely cause?

⚠ Common exam trap

AWS often tests the distinction between resource creation permissions and runtime invocation permissions, trapping candidates who assume that a successful stack deployment implies all runtime permissions are correctly configured.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

The agent role does not have permissions to invoke the knowledge base

The agent role must have an IAM policy that grants the `bedrock:Retrieve` and `bedrock:RetrieveAndGenerate` permissions on the knowledge base. Without these permissions, the agent cannot invoke the knowledge base, even if the KnowledgeBaseId is correctly passed and the embedding model is available.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
The KnowledgeBaseId is not passed correctly
Why it's wrong here
KnowledgeBaseId uses !Ref, which is correct.
✓
The agent role does not have permissions to invoke the knowledge base
Why this is correct
The agent's IAM role must have bedrock:InvokeKnowledgeBase permission.
✗
The embedding model is not available in the region
Why it's wrong here
The embedding model arn is region-specific and assigned via Sub.
✗
The OpenSearch collection type should be SEARCH not VECTORSEARCH
Why it's wrong here
VECTORSEARCH is correct for vector storage.

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AIF-C01 Applications of Foundation Models Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

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