Prototype

Prototype builds a disposable, project-local artifact so you can inspect an idea before deciding whether it deserves a real Build.

When to use

• You want to test whether an approach is worth pursuing.
• You need something to look at, not something to ship.
• You want to compare how different models tackle the same sketch.

What it does

Prototype runs Frame, Plan, Act, Verify, Review, Close. (Analyze is omitted; research-first work belongs in Explore.)

• Frame defines the artifact and its claim limits, and fixes a prototype_root that all files stay under.
• Plan chooses the disposable files to create.
• Act relays the work to an implementer, who writes the artifact.
• Verify runs an artifact-integrity check against the reported files.
• Review asks what to do with the result.
• Close emits the result with evidence links.

Prototype only creates files under prototype_root. It never edits production code, and it never claims deployment, branch previews, screenshots, or production readiness.

Variants

With --tournament, Act fans out one implementer per configured model variant. Each variant writes its own artifact under its own root; Circuit verifies them, relays a comparison to a reviewer, and ranks them. This needs circuits.prototype.variant_models in your config, one model per branch.

Checkpoints

After the artifact is verified, a checkpoint decides what happens to the prototype. At high process or in a tournament run, Circuit pauses for your call; otherwise it auto-resolves to the safe default, Keep Prototype (see Checkpoints). The choices:

• Keep Prototype: save it as evidence and stop.
• Save Build Input: close with a Build-ready follow-up prompt, without running Build.
• Discard Prototype: mark it discarded, keep the evidence trail.

In a tournament run, the checkpoint instead asks which verified variant to keep.

Example

/circuit:run prototype a command palette

circuit run prototype --goal 'sketch a custom flow builder UI'

Fan out across variant models:

circuit run prototype --goal 'compare command palette layouts' --tournament 3

Configure circuits.prototype.variant_models first, or the run exits without producing files.