Python package — TS parity port (framework_agents)

The TypeScript package (packages/typescript) is the reference implementation. This port targets API parity with the fixed TS semantics — every behavior that was a real bug during the TS line (and is regression-pinned there) is encoded here from day one:

No personal or brand names appear anywhere in this package.

Port status (mirroring the TS module map)

Batch-2 middleware (model_fallback, summarization, context_editing + ClearToolUsesEdit, llm_tool_selector, tool_emulator, filesystem, create_sub_agent, pii tool-results) is ported with deviations pinned in middleware.py's docstring (feedback-strings instead of raises on escape misses; older_than_steps interpreted as a step gate).

Running

python3 -m venv .venv
.venv/bin/pip install -e ".[dev]"
.venv/bin/python -m pytest tests -q                 # offline parity suite (233 tests)
E2E_MODEL=1 .venv/bin/python -m pytest tests -q -m live
# live Together parity runs; OpenAI + Anthropic suites skip cleanly and go
# live as soon as OPENAI_API_KEY / ANTHROPIC_API_KEY appear in framework/.env

Known deviations (documented in module docstrings)

• Agent.stream() yields a done event and stores the result (generators can't return values); run() drains — wire contracts identical.
• Async file IO runs via asyncio.to_thread in filesystem tools; storage classes use blocking IO inside async methods (single-process locality).
• Sandbox JS cannot hard-interrupt a thread mid-statement (node:vm can) — the timeout surfaces per contract, the abandoned thread dies at exit.
• Semantic version graphs use urn:framework:ontology:<version> (the TS default urn:fabisch:* embeds a personal name; both are configurable).
• Cross-language conformance: the Python A2A client speaks the exact wire contract of the TS A2A server (envelope, SSE frames, [DONE]) and vice versa — see tests/test_servers_and_clients.py.