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

With no annotations, the description carries the full transparency burden. It does well by disclosing the multi-source nature (NVD, CISA KEV, FIRST EPSS) and enumerating the exact data fields returned. It does not cover edge cases like unknown CVE IDs or output format, but there is no contradiction and the core behavior is clearly communicated.

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 efficient sentences with no fluff. The action and subject are front-loaded, the return fields are compactly enumerated, and every clause adds useful information. Excellent structure.

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?

The tool is a straightforward single-parameter lookup, and the description sufficiently explains what will be returned and from which sources. Minor gaps exist because there is no output schema and no mention of invalid-CVE behavior, but for this level of complexity the description is largely complete.

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% (single cve_id with an example), so the baseline is 3. The description restates that the tool looks up a CVE by ID, which adds no semantic depth beyond the parameter name and example. It meets the baseline without exceeding it.

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 a specific action ('Look up a CVE by ID') and a defined resource with a detailed summary of returned data. It does not explicitly differentiate itself from siblings like epss_score or known_exploited, which overlap in the EPSS and KEV content, so it falls short of a 5.

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?

Usage is implied: use this when you need a CVE summary. However, the description does not mention when to prefer a specialized sibling tool (e.g., epss_score for EPSS-only, known_exploited for KEV-only), leaving the choice ambiguous given that cve_lookup also returns those data points.

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