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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety is covered. The description adds real value by disclosing the breadth of the returned payload and its provenance (ledger version ranges, CSAF advisories, public exploit repositories) and flags that the remediation guide is conditional ('when one is published'). It stops short of describing not-found handling or any latency/caching behavior.

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?

A single front-loaded sentence with no filler; the resource is named first and the data enumeration follows. The list of payload categories is long but each item earns its place by telling the agent what evidence is available, and it never buries the core purpose.

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 must carry the burden of explaining what comes back, and it does so thoroughly, including the conditional remediation guide. The only gap for a one-parameter lookup of this complexity is the absence of any statement about missing/deprecated CVE ids or partial data availability.

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?

There is a single parameter with 100% schema description coverage, including a CVE-2026-1234 example, so the schema carries the load and baseline 3 applies. The description adds no format, normalization, or validation detail beyond what the schema states.

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 opens with a specific verb and resource: 'Full record for one CVE', then enumerates the payload (description, CVSS, EPSS, KEV/SSVC, affected products, advisories, exploits, remediation guide). This clearly distinguishes a single-record fetch from a list-style sibling such as search_cves or product_cves, though it never names an alternative explicitly.

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 only implied: an agent can infer this tool is for when it already has a CVE id and needs the complete record. There is no explicit when-to-use statement, no mention of when a lighter call (e.g. search_cves) suffices, and no note on behavior for unknown or malformed CVE ids.

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