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Bedrock Runtime

Protocol: REST JSON Endpoint: POST http://localhost:4566/model/{modelId}/...

Floci emulates the AWS Bedrock Runtime data-plane API with a dummy response stub. The response shape matches the real AWS Converse and InvokeModel contracts so AWS SDK and CLI clients accept the reply without error. No real model inference is performed: every call returns a fixed assistant turn plus synthetic token usage metadata.

The Bedrock management plane (aws bedrock ...: ListFoundationModels, GetFoundationModel, customization) is not yet emulated.

Supported Operations

Operation Endpoint Notes
Converse POST /model/{modelId}/converse Returns static assistant message
InvokeModel POST /model/{modelId}/invoke Returns Anthropic-shaped body for anthropic.* and *.anthropic.* model ids; generic {"outputs": [...]} shape otherwise
ConverseStream POST /model/{modelId}/converse-stream Returns 501 UnsupportedOperationException
InvokeModelWithResponseStream POST /model/{modelId}/invoke-with-response-stream Returns 501 UnsupportedOperationException

modelId is URL-decoded by JAX-RS and echoed verbatim. Plain model ids (e.g. anthropic.claude-3-haiku-20240307-v1:0), inference-profile ids (e.g. us.anthropic.claude-3-5-sonnet-20241022-v2:0), and full ARNs containing slashes (e.g. arn:aws:bedrock:us-east-1:123456789012:inference-profile/us.anthropic.claude-3-5-sonnet-20241022-v2:0) are all accepted.

Converse accepts messages, system, inferenceConfig, and toolConfig fields. Only messages is validated (non-empty array). Other fields are accepted and ignored. Tool-use round-tripping is not implemented.

InvokeModel bodies are passed through as opaque bytes; the stub does not parse request payloads.

Configuration

floci:
  services:
    bedrock-runtime:
      enabled: true

Examples

export AWS_ENDPOINT_URL=http://localhost:4566
export AWS_DEFAULT_REGION=us-east-1
export AWS_ACCESS_KEY_ID=test
export AWS_SECRET_ACCESS_KEY=test

# Converse
aws bedrock-runtime converse \
  --model-id anthropic.claude-3-haiku-20240307-v1:0 \
  --messages '[{"role":"user","content":[{"text":"hi"}]}]'

# InvokeModel (Anthropic Claude)
aws bedrock-runtime invoke-model \
  --model-id anthropic.claude-3-haiku-20240307-v1:0 \
  --body '{"anthropic_version":"bedrock-2023-05-31","max_tokens":100,"messages":[{"role":"user","content":"hi"}]}' \
  --cli-binary-format raw-in-base64-out \
  /tmp/response.json
cat /tmp/response.json

import boto3
client = boto3.client("bedrock-runtime", endpoint_url="http://localhost:4566")
resp = client.converse(
    modelId="anthropic.claude-3-haiku-20240307-v1:0",
    messages=[{"role": "user", "content": [{"text": "hi"}]}],
)
print(resp["output"]["message"]["content"][0]["text"])

Out of Scope

  • Real model inference (always returns a fixed string).
  • Streaming (ConverseStream, InvokeModelWithResponseStream) return 501.
  • Bedrock management plane (ListFoundationModels, GetFoundationModel, model customisation).
  • Bedrock Agents, Knowledge Bases, Guardrails, provisioned throughput.
  • Tool-use round-tripping in Converse.