[ docs · concepts ]
The ladder & rungs
The ladder is Grist's model lineup, organized the way the money works: four cost-tiered rungs, each holding the best model in its band. You work with rung names — never vendor model ids.
The rungs
| Rung | For | Character |
|---|---|---|
cheapest | Routine edits, renames, test fixes, formatting, small scripts | The default. Most tasks in a real codebase live here. |
medium | Everyday features, multi-file changes with a pattern to follow | The workhorse for substantive but well-understood work. |
frontier | Hard diagnosis, cross-subsystem design, subtle bugs | Exception, not habit — the gate escalates only on evidence. |
premium | The hardest, highest-stakes problems | The top band, reserved for when nothing else will do. |
Each rung is a cost band, not a capability class: the model behind a rung is whichever model currently wins that band, and it can change without your workflow changing. That's the point of naming rungs instead of models — your prompts, scripts, and habits survive model turnover.
Who decides
The Jev gate decides, once per run, from the task itself. Subagent delegations re-gate under the parent's rung as a ceiling, so breaking work down never inflates its price.
You can pin a rung when you really mean it:
grist run -m grist/frontier "diagnose the double-charge in checkout"Pinning is an override, not the workflow — left alone, the gate is better at this than habit is.
Your ladder, your key
- Dashboard overrides. Any rung can be pointed at a different model from your dashboard; the gate then routes among your choices.
- BYOK. Inference runs on your provider key — OpenRouter, Vercel AI Gateway, or any OpenAI-compatible endpoint — billed by your provider at zero markup. See gateway & keys.
- Hard caps. Spend caps are enforced before calls are made; an over-cap request returns 402, not a bill.
The client — CLI, TUI, desktop, API — only ever names rungs. Vendor model ids exist in exactly one place: the gateway's resolution of rung to model, where they can be governed, priced, and swapped.