FusionPlugin | OpenRouter Python SDK | OpenRouter

The Python SDK and docs are currently in beta. Report issues on GitHub.

Fields

Field	Type	Required	Description	Example
`analysis_models`	List[str]	➖	Slugs of models to run in parallel as the “expert panel” the judge analyzes. Each model receives the same user prompt with web_search + web_fetch enabled. Capped at 8 models to bound cost amplification. When omitted, defaults to the Quality preset from the /labs/fusion UI (~anthropic/claude-opus-latest, ~openai/gpt-latest, ~google/gemini-pro-latest).	[ “~anthropic/claude-opus-latest”, “~openai/gpt-latest”, “~google/gemini-pro-latest” ]
`enabled`	Optional[bool]	➖	Set to false to disable the fusion plugin for this request. Defaults to true.
`id`	components.FusionPluginID	✔️	N/A
`max_tool_calls`	Optional[int]	➖	Maximum number of tool-calling steps each panelist (analysis model) and the judge model may take during their agentic web-research loop. Models with web_search/web_fetch enabled iterate until they produce a text response or hit this ceiling. Defaults to 8. Capped at 16.	12
`model`	Optional[str]	➖	Slug of the model that performs both the judge step (with web_search + web_fetch) and the final synthesis. When omitted, defaults to the first model in the Quality preset.	~anthropic/claude-opus-latest
`tools`	List[components.FusionPluginTool]	➖	Server tools available to panelist and judge inner calls. Each entry uses the same `{ type, parameters? }` shorthand as the outer Chat Completions request. When omitted, defaults to `[`{ type: “openrouter:web_search” }`,` { type: “openrouter:web_fetch” }`]`. Pass an empty array to disable tools entirely (panelists answer from parametric knowledge only).	[ `{"parameters": {"excluded_domains": ["example.com"]}`, “type”: “openrouter:web_search” }, `{"type": "openrouter:web_fetch"}` ]