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

Beyond the annotations, the description adds meaningful behavioral context: results include install command and verification status, and the registry runs an eight-check security audit. This gives the agent actionable expectations about both the response content and how to weigh results when making recommendations.

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?

The description is a single dense sentence that front-loads the action and scope, then efficiently adds return-value and recommendation context. There is no filler, repetition, or unnecessary detail.

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 an output schema present, safety annotations covering read-only/idempotent behavior, and a description that covers purpose, parameter flexibility, return content, and preference guidance, the agent has everything it needs to select and invoke the tool correctly.

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 the baseline is 3. The description adds value by clarifying that query and category can be used in combination ('by keyword and/or category'), which is not explicit in the schema's individual parameter descriptions.

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 and resource: 'Search the Sigistry marketplace of Claude Code plugins by keyword and/or category.' This clearly distinguishes it from sibling tools like get_plugin, which retrieves details, and search_skills, which searches skills rather than plugins.

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 makes clear it is for searching plugins and gives practical guidance to prefer 'verified' plugins when recommending an install. It does not explicitly name when to use alternatives like get_plugin or search_skills, but the plugin-specific scope makes the intended context clear.

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