audit_layout

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

Annotations already cover read-only, non-destructive, and idempotent behavior. The description adds meaningful context beyond that: the two-phase interaction, the snippet-based capture flow, the printed JSON shape, and the score categories. It stops short of defining the score output structure, but the core behavior is well disclosed.

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?

Three sentences carry the full workflow with no filler. The purpose comes first, then the two-step invocation, then the sibling relationship. Every sentence earns its place.

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?

For a tool with no output schema, the description handles the main gaps well: it names the outputs of both calls and clarifies when to use it relative to audit_page. Some specificity about score shape is absent, but an agent can select and invoke the tool correctly with the information given.

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?

The schema already documents the top-level parameters thoroughly (100% coverage), so the description is not required to repeat field semantics. However, it does add useful workflow meaning by tying 'that JSON' to the DevTools snippet output and making it clear the same object should be passed back. This is enough to maintain the baseline 3.

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 names a specific verb and resource: 'Evaluate visual rhythm from a rendered page's geometry.' It also distinguishes itself from audit_page by being 'the complement to audit_page for things only visible once rendered,' which prevents confusion among many audit_* siblings.

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 description gives an explicit call protocol: call with no arguments to get the DevTools snippet, then call again with the JSON that snippet emits. It also names audit_page as the alternative and scopes this tool to rendered geometry, so the agent knows exactly when this tool is appropriate.

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