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

Annotations already establish read-only and closed-world behavior. The description adds value beyond them by disclosing the return payload (slug, name, colors, first preview image, links to detail page and editor), which matters since there is no output schema. It omits ordering and whether results are paginated beyond limit.

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 tight sentences with no waste; the core action leads, filtering follows, and the return shape closes. Each 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 read-only list tool with a single sibling detail-fetch, the description covers purpose, filtering, and return fields adequately given the fully documented schema. Minor gaps remain around result ordering and total counts, but nothing an agent needs to invoke it correctly is 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 coverage is 100%, so every parameter is already documented in the schema. The description restates the same filter dimensions (category, style, free, keyword) without adding syntax, matching behavior, or default details, so 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?

States a specific verb (Browse) and resource (published App Store and Google Play screenshot templates), plus the fields returned. It does not explicitly name the sibling get_template or clarify list-vs-single, but the 'browse...templates' framing makes the distinction inferable.

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?

'Filter by category, visual style, free tier, or a keyword' implies the browsing use case, but there is no statement of when to use this versus get_template or get_screenshot_specs, and no prerequisites or exclusions.

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