Setup pstack

Configure one portable model sheet for the current parent harness. Read provider-dispatch.md and the model catalog before probing or writing anything. The dispatch rules, descriptor grammar, and the catalog's model matrix, kept predecessors, and route table are the contract. Choose one requested effort per assigned matrix family. Do not add a second configuration file, a runtime resolver, or a weaker-model fallback.

Resolve <config-home> once using the harness config-home rule. Use it for all current-state reads, writes, snapshots, restoration, and readback.

Claude Code writes <config-home>/pstack-models.md and loads it from <config-home>/CLAUDE.md using the import rule in step 8. When <config-home> is the default home, render exactly the legacy line:

@~/.claude/pstack-models.md

Only when CLAUDE_CONFIG_DIR redirects the home, render exactly @./pstack-models.md, relative to the importing file's directory.

Codex writes <config-home>/pstack-models.md. Codex has no @ include, so mirror the sheet's exact bytes inside one bounded block in <config-home>/AGENTS.md and retain the sheet as the editable source of truth: