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# FusionServerToolConfig - Python SDK

The Python SDK and docs are currently in beta.
Report issues on [GitHub](https://github.com/OpenRouterTeam/python-sdk/issues).

Configuration for the openrouter:fusion server tool.

## Fields

| Field                   | Type                                                                                                        | Required             | Description                                                                                                                                                                                                                                                                                                                                                             | Example                                                                                                                                                      |
| ----------------------- | ----------------------------------------------------------------------------------------------------------- | -------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `analysis_models`       | List\[*str*]                                                                                                | :heavy\_minus\_sign: | Slugs of models to run in parallel as the analysis panel. Each model receives the user prompt with openrouter:web\_search and openrouter:web\_fetch enabled, then a judge model summarizes the collective output into structured analysis JSON. Capped at 8 models to bound cost amplification. Defaults to the Quality preset from /labs/fusion.                       | \[<br />"\~anthropic/claude-opus-latest",<br />"\~openai/gpt-latest",<br />"\~google/gemini-pro-latest"<br />]                                               |
| `max_completion_tokens` | *Optional\[int]*                                                                                            | :heavy\_minus\_sign: | Maximum number of output tokens (including reasoning tokens) each panelist and the judge model may produce per inner call. Controls the total output budget so reasoning-heavy models like GPT-5.5 do not exhaust their token allowance before producing visible text. When omitted, the provider's default applies.                                                    | 16384                                                                                                                                                        |
| `max_tool_calls`        | *Optional\[int]*                                                                                            | :heavy\_minus\_sign: | 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]*                                                                                            | :heavy\_minus\_sign: | Slug of the judge model that produces the structured analysis JSON. Defaults to the model used in the outer API request.                                                                                                                                                                                                                                                | \~anthropic/claude-opus-latest                                                                                                                               |
| `reasoning`             | [Optional\[components.FusionServerToolConfigReasoning\]](../components/fusionservertoolconfigreasoning.md)  | :heavy\_minus\_sign: | Reasoning configuration forwarded to panelist and judge inner calls. Use this to control reasoning effort and token budget for models that support extended thinking.                                                                                                                                                                                                   |                                                                                                                                                              |
| `temperature`           | *Optional\[float]*                                                                                          | :heavy\_minus\_sign: | Sampling temperature forwarded to panelist and judge inner calls. When omitted, the provider's default applies.                                                                                                                                                                                                                                                         | 0.7                                                                                                                                                          |
| `tools`                 | List\[[components.FusionServerToolConfigTool](/docs/sdks/components/components/fusionservertoolconfigtool)] | :heavy\_minus\_sign: | 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). | \[<br />`{"parameters": {"excluded_domains": ["example.com"]}`,<br />"type": "openrouter:web\_search"<br />},<br />`{"type": "openrouter:web_fetch"}`<br />] |