Setup pstack

Follow the portable runtime contract throughout this setup.

Write the optional pstack configuration at $PSTACK_CONFIG when that variable is set; otherwise use .pstack/config.md in the current project. This is an override layer, not a requirement. Never write to a vendor-specific home directory.

Steps

Model discovery and model assignment are different capabilities. A model listed by pi --list-models is available to the current Pi process, but that does not mean a workflow can send work to it. Per-role assignment also requires a host task or subagent facility that accepts a model choice. Native Pi intentionally does not include subagents. Do not claim that a role was assigned when that facility is absent.

Pi delegation prerequisite

For native Pi, recommend the maintained pi-subagents package when the user wants parallel workers or per-role models: