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

With no annotations, the description carries the full burden and does well: it discloses that access is keyless, that NVD is rate-limited without a key, and that the operation is read-only. It does not state failure behavior for unknown/malformed CVE IDs, which keeps it short of 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 tight sentences that are front-loaded with the action and resource, then pack return fields, input provenance, auth/rate-limit, and safety into the remainder. No sentence is filler.

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?

There is no output schema or annotation coverage, so the description must stand alone — and it does, enumerating the return payload, the input expectation, provenance, and operational constraints. An agent has everything needed to invoke 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?

Only one parameter, and schema description coverage is 100% with the example 'CVE-2021-44228' already embedded in the schema. The description adds the notion of a 'bare CVE ID' but no format rules, accepted forms, or normalization behavior beyond what the schema provides, 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?

The description names a precise verb and resource ('Look up a CVE in the NVD') and enumerates exactly what is returned (description, CVSS base score/severity/vector, CWE IDs, dates, references), so the agent knows precisely what this does. It does not, however, differentiate itself from closely related siblings such as cve_triage, kev_check, or epss_score, which a 5 would require.

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?

'Turns a bare CVE ID (e.g. one from host_exposure) into meaning' gives a clear triggering condition and ties the tool to an upstream sibling, so the agent knows when to reach for it. It stops short of saying when NOT to use it or naming the alternative enrichment tools (cve_triage, kev_check, epss_score).

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