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

Annotations already declare readOnlyHint and idempotentHint, but the description adds non-obvious behavior: a hard cap of 20 items, the exact fields returned, and that each call consumes one request of the monthly quota. The quota cost is genuinely useful context an agent cannot get from annotations, though pagination/empty-result behavior is not addressed.

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 tight sentences with no filler: what it returns and ordering first, then return shape, then the routing hint and cost. Every sentence carries distinct information and the most decision-relevant facts are front-loaded.

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?

For a two-parameter read tool with no output schema, the description supplies the missing return contract (id, severity, CVSS, publication date, title), the result cap, and the quota cost, which is everything an agent needs to call and interpret it 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 description coverage is 100%, so both limit (default 10, max 20) and severity (enum of CRITICAL/HIGH/MEDIUM/LOW) are fully documented in the schema. The description restates the severity filter and the 20-item cap but adds no syntax or semantics beyond that, which is the expected baseline when the schema does the work.

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+resource ('Most recently published CVEs'), the ordering ('newest first'), and the optional severity filter, so an agent knows exactly what it returns. It also names the sibling get_cve as the detail-fetching counterpart, making it distinguishable from the other lookup tools.

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 explicitly routes follow-up work ('Follow up with get_cve for details'), which tells the agent to use this for discovery and get_cve for depth. It gives clear context but no explicit when-not-to-use case (e.g., searching by keyword or product, which search_indicators may cover).

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