mockup_grid

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

No annotations exist, so the description carries the whole burden. It discloses the visual behavior of region zooming to a finer grid, which is genuinely useful, but says nothing about what the tool actually returns (image data, a file on disk, a path), whether it writes anything, or any permission/cost constraints.

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?

Two short sentences, no filler, with the tool's purpose front-loaded and the region behavior following. Every clause contributes information the agent cannot get from the schema.

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?

With no annotations, no output schema, and 0% parameter coverage, the description should do more: the return format of a grid-overlay image tool is unspecified, and two of three parameters (path, step) are undocumented anywhere. Only region is adequately covered.

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 0%, so the description must carry the parameters. It does well for region, giving the exact [x, y, w, h] ordering and the effect of zooming to a finer grid, but path and step are never explained — step's default of 50 and its role in grid density are left entirely to inference.

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 states a concrete output: a page picture overlaid with a labelled pixel grid whose purpose is extracting coordinates for a design_page spec. That is specific enough to separate it from rendering siblings like render_page or render_region, though it never names those siblings to make the distinction explicit.

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 purpose chain is implied clearly: use this to read coordinates that a design_page spec needs. But there is no explicit 'use when / don't use when', no mention that it precedes design_page, and no reference to the alternatives (design_mockup, render_region) that could plausibly be confused with it.

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