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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), yet the description adds genuinely new operational context: per-call cost ($0.02 USDC via x402), where payment goes (_meta["x402/payment"]), that invalid input and upstream failures are not charged, and that claims are unverified leak-site data rather than confirmed breaches. That provenance caveat and billing model are exactly the kind of disclosure annotations cannot carry.

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?

Four tight sentences, front-loaded with purpose and output contents before secondary details (alternative tool, error semantics, disclaimer, pricing). No filler and no repetition of structured fields.

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 compensates by describing the returned fields and the sample-vs-full-list distinction, plus error and billing behavior. An agent has everything needed to call this correctly and interpret the result responsibly.

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 ('Ransomware group name or alias, e.g. akira'), so the schema already does the work. The description adds no format, casing, or matching nuances beyond what the schema states, 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?

States a specific verb and resource ('Get a profile of one ransomware group') and enumerates the exact contents returned: aliases, first-observed date, and a sample of newest claims. It explicitly distinguishes itself from the sibling recent_claims, so an agent can route without opening either schema.

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?

Gives positive guidance ('Use it to understand who a group is') and names the alternative with the condition that selects it ('use recent_claims for a longer list of its latest claims'). Error behavior for unknown groups (error, not charged) is also stated up front.

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