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

The annotations already declare readOnlyHint=true, and the description adds valuable behavioral context: it explains the score's statistical basis (z-scored against trailing year's four 90-day windows), lists the return fields (trend, z_score, recent_window_count, baseline statistics), and states 'Updates: daily.' This goes beyond the annotation without contradicting it.

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?

The description is two sentences, with the first sentence front-loading the primary purpose and calculation, and the second adding use cases and update frequency. Every phrase earns its place; there is no redundancy or 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?

Despite lacking an output schema, the description enumerates the key return fields and provides enough context about the metric. The optional days parameter is documented in the schema, so the description remains complete for the tool's complexity. Minor gap: it doesn't explain what 'trend' or 'z_score' mean precisely, but the overall picture is sufficient.

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% for the single 'days' parameter, so the schema fully documents it. The description does not elaborate on the parameter, which is acceptable given the schema's quality, meeting the baseline but not 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 the tool returns a 0-100 software CVE publication surge score and explains the calculation using NIST NVD data. The verb 'Returns' and the specific resource 'software CVE publication surge score' distinguish it from the opaque sibling tool names.

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 provides explicit 'Call when' guidance covering multiple use cases (CVE volume surges, vulnerability disclosure rates, patch-management load, software-risk exposure, timing patch-ops, scan cadence, cyber-insurance reviews). It lacks explicit when-not-to-use or named alternatives, but the context is clear and specific.

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