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Runs your task app locally on your machine. Useful for development and collecting traced rollouts.

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Usage

uvx synth-ai serve
Starts a local FastAPI server for your task app. You’ll be prompted to enable tracing (for collecting rollout data) and select which task app to run. Inputs:
  • Task app selection (interactive prompt if multiple apps found)
  • Tracing configuration (optional)
  • API keys for your environment (e.g., Groq)
Outputs:
  • Local server at http://0.0.0.0:8001 (or specified port)
  • Trace database (if tracing enabled)
  • Instructions for running rollouts

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Options

  • serve <APP_ID> - Skip prompt by specifying app ID
  • --port N - Change port (default: 8001)
  • --env-file PATH - Use a different .env file
  • --reload - Auto-restart on code changes
  • --trace PATH - Enable tracing and set output directory
Use this command when following the Fine-Tuning Demo to collect rollouts locally before training.
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