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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds value beyond that by enumerating the returned fields (skill id, publisher, description, latest version, trust tier), which matters because there is no output schema; it omits ranking or truncation behavior, keeping it below a 5.

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?

Two sentences, front-loaded with the verb and resource, and the second sentence carries return shape and the next-step handoff. No redundant restatement of the title or annotations.

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 takes on the burden of describing return fields, and it names the follow-up tool. Slightly incomplete on result ordering, page/limit interaction, and what a trust tier means, but nothing that would cause a mis-call.

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 both query and limit are already documented, including the empty-string browse behavior. The description's "by what they do" reinforces the query intent but adds no syntax, matching, or limit semantics beyond the schema, so the 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 and resource ("Find runx skills") plus the retrieval axis ("by what they do"), and explicitly positions itself relative to the sibling get_skill. An agent can immediately tell this is the discovery step, not the read step.

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?

Describes the intended workflow: search, pick a match, then read it in full with get_skill. That is clear context and a named alternative, though it gives no explicit when-not-to-use conditions (e.g., when to skip straight to get_skill with a known id).

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