Check

What check proves

Verify proves the project’s configured automated checks pass. Check proves the behavior described by the active spec can actually be observed. Passing CI does not replace this behavioral evidence. For a rollback, check includes proving the removed behavior is gone and an unaffected regression path still works.

Evidence

Depending on the project, evidence can include:

• Browser navigation, clicks, forms, and screenshots
• Console and network error inspection
• CLI output and exit status
• API requests and response bodies
• Generated files or downloaded artifacts

Report

Check reports pass or fail for every done-when criterion. A failed criterion includes the observed result and the next fix target. Check does not edit source code or commit fixes.

Try It Now and manual guide

New projects default tryGuide to when-testable. After Verify and any required Check pass, Blueprint automatically adds one small ## Try it now proof when the feature has a safe, meaningful direct observation path.

## Try it now

Run or do:
<the smallest useful command or interaction>

Expected:
<the exact visible output, response, file, or UI state>

This proves:
<the specific behavior directly observed>

The proof adapts to CLI output, library calls, API responses, UI interactions, generated files, configuration, or inspectable data. Documentation-only edits and invisible internal changes do not get fabricated instructions.

Run /check guide in Claude Code or $check guide in Codex when you want the proof explicitly or need a deeper walkthrough for trying the change yourself.

/check guide
/check guide latest
/check guide /settings

With no scope, the guide uses active work or the most recent archive when no work is active. latest selects the latest archive even while a feature is active. A step, route, path, or command can narrow the guide.

The guide explains what to start, where to go, what to do, what to expect, and what would indicate a problem. It never starts a development server. When the project requires you to start one, the exact command stays in your hands. It does not run the app or checks, edit files, write activity or spec status, or record acceptance. Only the selected mode’s instructions are loaded.

Default /check remains the agent’s verification pass. Try It Now is a user demonstration, not a replacement for tests, Verify, Check, or user acceptance. The tryGuide configuration keys select /check guide; the separate check gates still select verification.

The former /try command is replaced by /check guide. See migration guidance.