a2a_chat.py DOX

Purpose

• Own the a2a_chat.py agent tool.
• This module lets the agent message an external A2A agent and extract the assistant reply.
• Keep this file-level DOX profile synchronized with a2a_chat.py because this directory is intentionally flat.

Ownership

• a2a_chat.py owns the runtime implementation.
• a2a_chat.py.dox.md owns durable notes about responsibilities, contracts, side effects, and verification for that implementation.
• Classes:
• A2AChatTool (Tool)
  • async execute(self, **kwargs)
• Top-level functions:
• _session_key(agent_url: str) -> str: Keep root and explicit /a2a URLs in the same conversation cache.
• _text_from_part(part: Any) -> str
• _text_from_message(message: Any) -> str
• _extract_latest_assistant_text(task_response: Any) -> str
• Notable constants/configuration names: A2A_EMPTY_RESPONSE_ERROR.

Runtime Contracts

• Tool modules must define helpers.tool.Tool subclasses and return helpers.tool.Response from execute(...).
• Update this file whenever tool arguments, output shape, break_loop behavior, intervention handling, prompt instructions, or side effects change.
• A2AChatTool is a Tool.
• A2AChatTool defines execute(...).
• Observed side-effect areas: filesystem writes, scheduler state.
• Imported dependency areas include: helpers.fasta2a_client, helpers.print_style, helpers.tool, typing.

Key Concepts

• Important called helpers/classes observed in the source: agent_url.rstrip, normalized.endswith, _text_from_message, normalized.rstrip, message.strip, join, _session_key, value.strip, _text_from_part, is_client_available, Response, self.agent.get_data, sessions.pop, _extract_latest_assistant_text, PrintStyle.error, connect_to_agent, conn.send_message, conn.wait_for_completion, self.agent.set_data.
• Keep request/response, tool, or helper semantics documented here at the same time as source changes.

Work Guidance

• Keep tool output concise, model-readable, and safe for history persistence.
• Coordinate argument or behavior changes with prompt tool instructions and skill guidance.
• Respect intervention flow for long-running, external, or user-visible operations.

Verification

• Run targeted tool and prompt-contract tests for changed behavior; smoke-test agent execution when no focused test exists.
• Related tests observed by source search:
  • tests/test_tool_action_contracts.py

Child DOX Index

No child DOX files.