SiTaggart Setup pstack
Read PStack runtime guidance before this workflow.
Select the host through RUNTIME.md. Codex uses models.json and ~/.codex/pstack-models.json; Claude Code uses models.claude.json and ~/.claude/pstack-models.json. Read and write only that host’s override file. Missing roles keep the bundled default. These are PStack data, not global host settings.
Steps
1. Detect available models
Enumerate the model slugs you can pass to a native subagent in this session. That is the dependable source. Use the current subagent tool schema, including supported reasoning levels; a sidebar-task model list does not establish subagent availability. If you cannot detect any, ask the user to paste the slugs they have access to. Never write a real slug you have not confirmed is available. The aliases inherit-parent and auto are always valid even though they are not detected slugs.
2. Load current state
Use the selected host’s bundled mapping. If its override file already exists, read it and treat its values as the current choices over those defaults. Report invalid JSON rather than overwriting it.
3. Map and confirm
Show every role with its current model, marking any real slug not in the detected set as needing a choice. Ask whether to accept as-is or change specific roles, offering the detected models plus inherit-parent and auto (both mean: this role runs on the parent chat model, which is how Auto users stay on Auto) as the options. Prefer the available user-input tool over free text, within its supported schema. Reuse choices already supplied by the user. For panel roles (arena runners, architect runners, interrogate reviewers) the value is a list, and one subagent runs per entry, alias entries included, so the list length sets the count. arena cross-judge pool is also a list, but Arena selects one value from it that differs from the parent model when possible, per RUNTIME.md; each host’s defaults use models from one provider. swarm workers is the default model for every worker unless a race or comparison assigns another model per arm.
4. Validate
Every real slug written must be in the detected set. inherit-parent and auto always pass. If a chosen real slug is not available, stop and ask again.
5. Write the overrides
Write the selected host’s override file using its exact bundled role labels. Preserve existing choices the user did not change. Overwrite the complete merged JSON object so re-runs stay idempotent. Delete a role to return it to the bundled default. Each choice is a model string or an object with model and the host’s optional effort field (reasoning_effort for Codex, effort for Claude); panel roles take a non-empty list of choices. Validate role keys, single versus panel shape, supported models and reasoning levels before writing. Reject extra object fields. inherit-parent and auto omit both model and effort. Follow RUNTIME.md for runtime fallback and dispatch.
Example shape for two overrides (leave other roles at their existing or bundled values):
{
"feature, refactoring": "inherit-parent",
"hardest tasks": "inherit-parent"
}
6. Confirm
Parse and read back the saved JSON. Tell the user the overrides were written and that subsequent PStack invocations read them. Re-running this skill updates them.
7. Offer a verification skill (optional)
Check whether the project has a way to drive the real app for proof (a verify-* skill, or an existing harness). If not, offer once: "want a project-local verification skill, so agents can drive the app the way a user does and prove changes work? I can generate one with /create-verification-skill." On yes, invoke /create-verification-skill (resolves wherever pstack is installed: workspace, user, or plugin). On no, move on without pushing.