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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful context the annotations cannot: the shape of the result (skill names with a one-line summary, practice area and access level), which matters because there is no output schema. It stops short of noting pagination or that results are capped by the limit parameter.

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?

Front-loaded with the purpose, followed by examples, return shape, and the sibling pointer — every sentence does work. The four quoted example queries occupy a substantial share of the text, which is helpful but slightly padded for a tool whose input is plain prose.

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 output schema, the description correctly compensates by describing the returned fields, and the annotations carry the safety profile. The only real gap is that list_skills is never addressed, leaving the agent to infer whether enumeration is an alternative.

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%, so all three parameters (query, area, limit) are already documented with constraints and enum values. The description's example queries illustrate what a good 'query' looks like, but adds nothing about 'area' or 'limit' beyond the schema. Baseline 3 is appropriate.

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 and resource ('Search the skills library by task, tool or problem') with concrete query examples that make the retrieval mode unambiguous. It also names the sibling get_skill as the follow-up for reading a result, so an agent can distinguish this from its siblings without opening a schema.

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?

Explicitly routes to 'get_skill next to read one', which tells the agent when to use this tool versus continuing with get_skill, and the four example queries demonstrate the intended input mode. It does not mention list_skills or state when browsing/enumeration is preferable to searching, so the sibling routing is partial rather than exhaustive.

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