prime-rl Post-Training

prime-rl is Prime Intellect's framework for asynchronous RL and SFT post-training at scale. One launch (uv run rl) starts a vLLM inference server, a CPU-only orchestrator that collects rollouts from verifiers environments, and an FSDP trainer that pushes new weights back to inference. This skill teaches how to install it, write configs, choose an algorithm, launch and monitor runs, evaluate checkpoints, and export weights.

Facts are checked against upstream commit dd72f0f (2026-10-13, v0.9.0). When the docs and the code disagree, this skill follows the code (see Doc Drift).

Quick Reference