Verify page

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does much of it: it discloses that a real Chromium browser is launched, that checks run per viewport, what artifacts are produced, and includes a workflow directive. What remains undisclosed are operational traits such as timeout/wait behavior, whether it requires the target server to be up, or any rate/side-effect profile.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the action and a single dense sentence enumerating outputs, followed by a crisp two-clause directive. The output list is long but each item earns its place; only minor tightening of the run-on sentence is possible.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, so the description correctly enumerates the return payload, which is the most important completeness factor here. With 6 well-documented parameters and no annotations, it is nearly sufficient; only environment prerequisites and failure/timeout behavior are missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so every parameter is already documented in the schema (including the viewport defaults and the 200-4000px / deviceScaleFactor 1-4 bounds). The description restates the default viewports but adds no syntax or edge-case detail beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description gives a specific verb and resource (opens a URL in Playwright Chromium across viewports and verifies the page) and enumerates exactly what is checked: screenshots, console errors, failed requests, overflow, axe-core violations, ARIA snapshot, pointer type. An agent can immediately tell this is a visual/accessibility verification tool, clearly distinct from the sibling frontend_stack_pipeline and list_styles.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The closing line 'Look at the screenshots before calling a build done' gives one workflow cue for when to invoke it, but there is no explicit when-not guidance, no named alternatives, and no statement of prerequisites (e.g. a running dev server). Usage is implied rather than specified.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.