Verify

Try to demonstrate a break in the change. Each check tests a concrete failure hypothesis against current artifacts. Save the outcome in the task file's ## Verify section, then send failures to uexecute or advance to ureview.

Read the brevity rules before responding or writing results. Passed checks take one line. Failures, deferrals, and surprising results carry evidence and reasons.

Phase 1 — Build the attack list

Build hypotheses from the plan, design constraints, assumptions, interfaces, and your own inspection. Number them CK1 through CKN within the task file. Keep the working list in-session until writing the results.

Cover these angles:

• Valid input: find a supported input, environment, ordering, or retry that the change mishandles.
• Invalid input: find missing values, type confusion, or malformed input that bypasses validation or raises the wrong error.
• Invariants and assumptions: try to violate each relevant guarantee or disprove an external premise. Reference its design ID.
• Interfaces: find callers, outputs, or documentation references that disagree with the declared contract. Reference its interface ID.

For example, an item endpoint should reject name: null as a client error. Test whether it instead reaches the handler and returns a server error. "Test the happy path" is not a failure hypothesis.

Phase 2 — Run each attack freshly

Run the attacks during the current verification. Previous-session results do not establish the current state.

• Use minimal direct probes, following try's approach. One-off scripts belong in gitignored, project-local tmp/ and are removed after use.
• Capture actual commands and output. Inspect what happened before deciding the verdict.
• A failed attempt to break the change is a valid outcome when the probe ran and the evidence supports it. An unavailable probe is a deferral, not evidence that the condition held.
• Respect user authorization for expensive or remote checks. Report missing permission rather than running them or claiming success.

Phase 3 — Smoke the end-to-end

Run the shortest representative full path: invoke a changed command, call the running endpoint, exercise the interface in a browser, or run a small model step when authorized.

A failing smoke is a demonstrated break. A passing smoke does not replace the other attacks. If it cannot run, name the blocker. Do not substitute a unit test and call it a smoke.

If the smoke is only a proxy for the goal, state what it covers and what remains. A small local sample does not establish success for a full remote dataset. Goal validation must retain that distinction.

Phase 4 — Write the Verify summary

Append or replace ## Verify in the task file, whether the outcome passed or failed.

• held: the attack ran and demonstrated no break.
• broke: the attack demonstrated a break. Include evidence and expected behavior.
• deferred: the attack could not run. Name the blocker and justification.

Set Result: passed only when every check held or has a justified, user-visible deferral. Any broken check makes the result failed. Never label an unrun check held.

## Verify

Result: <passed | failed>

Happy-path:
- CK1 — <hypothesis> — <verdict>

Negative:
- CK2 — <hypothesis> — <verdict>

Invariants / assumptions:
- CK3 (IV1) — <hypothesis> — <verdict>
- CK4 (AS1) — <hypothesis> — <verdict>

Interfaces:
- CK5 (IF1) — <hypothesis> — <verdict>

Smoke: <command and result>
Goal: proxy only — <coverage and remaining real-world validation>
Notes: <failure evidence, expected behavior, deferrals, or reruns>

Omit empty categories. Omit Smoke if it did not run, but record the blocker in Notes. Omit Goal when the smoke covered the actual goal. Omit Notes only when there is no failure, deferral, or other material evidence to report.

Example failure:

## Verify

Result: failed

Negative:
- CK2 — null name on item creation — broke: null reached the handler and raised TypeError, returning 500 instead of 400.

Notes: reject null, empty, and whitespace-only names before the handler runs. Return to execution with this reproduction.

Phase 5 — Handoff

• Every check held or was justifiably deferred: report verification passed and invoke ureview, preserving deferrals and remaining goal validation.
• Any check broke: describe the intended behavior under that input, include the reproduction, and invoke uexecute. Do not advance to review.

Future work and incomplete work

In-scope requirements remain part of this task. Complete them or obtain user consent to change scope.

A future-work entry requires a design-scope line excluding it or a newly discovered fact that changes scope. Record that justification. Do not relabel a required failing check as future work to pass verification.

Never

• Claim a check held without running it during the current verification.
• Declare pass when an attack broke.
• Treat a clean diff, lint result, ordinary unit-test result, child assertion, or confidence statement as an adversarial verification by itself.
• Claim there is no way to break the change without naming the angles tried.
• Skip verification or rely on a prior session's verdict.

Hands-off mode

Read handsoff. The pass-to-review and fail-to-execution loop is unchanged. Record infeasible smoke tests under ### Deferred (needs user input) with the blocker. Never fabricate success.

Terminal state

The summary is saved. Pass returns to review. Failure returns to execution with evidence and intended behavior.