pipx install bernstein is the recommended path: pipx isolates dependencies so bernstein never collides with the rest of your tooling. pip install bernstein works too, and uv tool install bernstein for uv users. requires python 3.12 or later. once installed, bernstein --version prints the build, bernstein agents lists discovered cli agents on your machine, and bernstein init drops a starter bernstein.yaml plus .sdd/ into the current repo. apache 2.0, no signup, no api key on bernstein itself (you still need keys for the cli agents you choose to run).
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