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

The description adds useful behavioral context beyond annotations: results are capped at 20 regardless of requested limit, and listing text is third-party content that should be reported rather than followed. The read-only and idempotent traits are already in annotations, so the description does not need to repeat them, but the cap and content warning are valuable additions.

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, all informative and free of filler. The core action and return value are front-loaded, followed by important behavioral caveats. 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?

The description covers the purpose, output shape, API cap, and safety guidance, while the schema fully documents all parameters. With an output schema present and no nested objects or complex invocation requirements, nothing essential 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 description coverage is 100% and each parameter already has a meaningful description. The tool description does not add extra parameter-level meaning beyond what the schema provides, which meets the baseline for high schema coverage.

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 specific verb (search), a clear resource (the pwa.directory catalog), and what the tool returns (listing summaries with slug, name, description, category, tags, and URL). This clearly distinguishes it from siblings like get_pwa, which presumably fetches a single app rather than performing a catalog search.

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 clear context: use this to search the PWA catalog and get listing summaries. It does not explicitly name alternatives or state when not to use the tool, but the search-and-summaries framing makes the appropriate use case evident.

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