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AnthropicMessagesToolResponseAdapter is the default ToolResponseAdapter used whenever you pair an agent with the Anthropic Messages adapter. It converts tool outputs into Anthropic tool_result blocks and provides a plain-text fallback that hosts can display or log.

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Behavior summary

  • Plain-text rendering: to_plain_text generates concise strings for common response types (LinkResponse, JsonResponse, TextResponse, FileResponse, EmptyResponse).
  • Chat context updates: create_messages returns a user message containing a tool_result block so the model can consume tool output on the next turn.
  • Attachment handling: Images and PDFs are converted into Anthropic image or document blocks; unsupported image types fall back to text.
  • Developer logging: Emits events via room.developer.log_nowait to aid debugging when tools are called.

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Response handling

Response typePlain text exampleNotes
TextResponseThe returned textIncluded as a text block in the tool_result.
JsonResponseJSON string dumpIncluded as a text block in the tool_result.
FileResponsefilename.extImages (image/jpeg, image/png, image/gif, image/webp) are embedded as Anthropic image blocks; PDFs become document blocks; other files fall back to text.
LinkResponse{ "name": ..., "url": ... }Serialized to JSON and included as a text block.
EmptyResponse"ok"Signals successful execution without additional data.
RawOutputsn/aPassed through directly as Anthropic message blocks, bypassing plain-text conversion.

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Tool use requirements

Anthropic requires tool results to include a tool_use_id. The adapter raises an error if the tool_use block is missing an id.

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Extending or replacing

You can subclass AnthropicMessagesToolResponseAdapter to customize plain-text formatting or message content, provided the emitted messages still follow Anthropic’s tool_result schema. Alternatively, supply your own adapter instance when constructing the agent (for example, ChatBot(..., tool_adapter=...)).

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Where it is used

  • Automatically when you construct AnthropicMessagesAdapter without specifying a custom tool_adapter.
  • Any agent that wants to reuse the same Anthropic formatting logic can import and instantiate it directly.