v0.5.0

MMSP 0.5.0 is AgentHub under its new name, the Model Message Stream Protocol, and the first release on streaming protocol v2. It is a breaking release: the packages, the module, the client types and the stream shape all change, and the compatibility notes below say what to update.

Highlights

• AgentHub is now MMSP. The packages are mmsp on PyPI and @prismshadow/mmsp on npm, the module is mmsp, the error base class MMSPError, and the environment variables MMSP_DEBUG and MMSP_CACHE_DIR (#223).
• Streaming protocol v2. A stream is delta events closed by exactly one stop event, and every content item streams as .delta fragments closed by its .done item, so a consumer never guesses whether a response or an item has finished. Content items recorded before 0.5.0 are still accepted, converted to the .done types, until 0.6.0 (#223).
• Clients are named by type. An official client per vendor (openai-official, anthropic-official, gemini-official, zai-official, moonshot-official, deepseek-official, minimax-official) and a compatible client per protocol (openai-responses, openai-chat, openai-chat-vllm-adapter, openai-embedding, ant-messages, gemini-generate-content). Without a client_type, the family a model id begins with names its official client; any other id asks for one (#228).
• Gemini on the Interactions API. Gemini text, image and TTS models move to the Interactions API on google-genai / @google/genai 2.x, and a Vertex AI service-account key goes through generateContent (#223).
• New models. Claude Opus 5.5, Sonnet 5.5 and Fable 5.1, GPT-6.1 Sol, DeepSeek Flash and Gemini 3.8 TTS, with two-speaker scripts sent to 3.8 TTS as per-turn speech metadata (#229).
• Credentials stay with their endpoint. OPENAI_API_KEY and ANTHROPIC_API_KEY go only to the endpoint the environment names, and a base_url without an api_key raises (#224).
• A new playground, tracer and site. The playground sets the client type and base URL with the model and shows every stream item as it arrives; the tracer reads traces as aligned lists with a round rail; the documentation lives at https://mmsp.penguin.ooo (#226, #227, #229, #231).

Compatibility

• Install mmsp / @prismshadow/mmsp in place of agenthub-python / @prismshadow/agenthub, and import mmsp.
• Read items by their .done types (text.done, thinking.done, tool_call.done …) and treat .delta fragments as live progress.
• Replace the model-named client types with the new ones (for example gpt-6 → openai-official, claude-5 → anthropic-official); a gateway model id such as moonshotai/kimi-k3 now needs its client_type.

Install

pip install mmsp==0.5.0
npm install @prismshadow/mmsp@0.5.0

Full detail: changelog/0.5.0/README.md.