What problem does it solve? End-to-end tests break when elements lack stable selectors, forcing fragile locators based on copy, CSS classes, or DOM position. This Skill closes that gap by adding one inert test attribute (data-testid or the project's detected convention) to the offending element and proving the change has zero functional or visual impact before resuming test authoring. ## Core Features & Use Cases - JIT mode: Instruments exactly one element with one attribute in one round-trip, triggered from Stage 2 inspection escalation, failure-diagnosis of fragile selectors, or a direct user request. - Audit mode: Iterates the journey map page-by-page to instrument every interactive or asserted node lacking a stable selector, with a ledger for deduplication and resumption. - 8-step guardrail pipeline: Enforces before/after screenshots, typecheck, unit tests, e2e run, visual diff (0-pixel threshold), and commit via hook-gated receipts, with automatic revert on any failure. - Use Case: A Playwright spec fails because the checkout button has no stable locator. The Skill appends data-testid="submit-button" to the button's opening tag, runs the full guardrail pipeline, commits the change, and returns control to the test-authoring workflow. ## Quick Start Ask the agent to add a stable selector to the checkout button so the failing e2e spec can target it reliably.
