Skip to main content
Use phaseo:fusion when one answer benefits from several independent model perspectives. Phaseo runs the analysis models in parallel, then asks the selected analyst model to synthesize their findings for the calling model.

​
Playground setup

In the Playground server-tools menu, Fusion lets you choose:
  • analysis models that independently inspect the request
  • an optional judge model that compares the analysis outputs
  • a max tool-call limit for the Fusion advisor tools
The main model sees those named advisors during the same tool loop and can use their outputs before writing the final response.

​
API shape

​
When to use Fusion

Use Fusion for:
  • planning decisions where a second or third model may catch missing assumptions
  • research synthesis where models may weigh evidence differently
  • code or architecture reviews where you want independent critique
  • high-value responses where a little extra latency is acceptable
Use a single Advisor instead when you only need one review pass.

​
Usage and pricing

Each Fusion invocation increments:
The advisor models’ tokens are included in total usage and can be priced at each selected advisor model’s rates. Server-tool pricing can also use server_tool_advisor_requests.
Last modified on October 18, 2026