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

Annotations already state readOnlyHint=true, so the description need not restate that. But it adds the non-billable trait synchronously, which is extra context. It does not describe return format details, but the schema coverage is highley explanatory.

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 concise, with no filler. It front-loads the purpose before query forms. Every sentence adds value, making it efficient and scannable.

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?

Given that this is a search tool with a simple input schema and no output schema, the description covers all necessary aspects: how to query, what to expect, and scope. No critical information is missing for correct use.

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 each parameter is fully described in the schema. The description adds extra meaning about query forms and behaviors (e.g., max_results ignored for select and skill) that go beyond the schema, enhancing semantics.

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 clearly states the tool's purpose: finding the right tool rather than guessing its name. It specifies the action (search), the resource (tools), and the output (full JSON schemas), which distinguishes it from siblings like list_skills.

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 provides explicit query forms with examples ('skill:<name>', 'select:name1,name2', free text) and conditions for use. It also mentions that 'skill:' queries should be used with list_skills for names, giving clear guidance on when to use this tool versus alternatives.

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