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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly discloses that it uses the npm 'semver' package (not a heuristic), and mentions the cost of '$0.01 USDC (Base) per call'. These are meaningful behavioral details beyond the schema, providing transparency about execution and pricing.

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 no filler. It opens with the core action, provides illustrative examples compactly, and ends with a cost note. Every sentence earns its place and the structure is front-loaded.

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?

Given that the tool has a rich input schema (100% param coverage) and an output schema (not shown but present), the description only needs to add missing context. It successfully does so by clarifying the authoritative engine (npm semver) and the cost per call. For a simple validation tool, this is complete and 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?

The schema already covers 100% of parameters with descriptions, so the baseline is 3. The description adds value by providing examples of accepted range formats ('^1.2.3', '~2.0', '2.x', '>=1.0.0 <2.0.0') and reinforces that evaluation follows npm's real semver logic, which helps clarify the semantics of the 'ranges' parameter beyond the schema's generic phrasing.

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's function: 'Resolves real semver range satisfaction' against a version, with concrete examples of range syntax. It distinguishes itself from a 'model guess' by specifying it uses the npm semver engine, which is more specific than merely restating the tool name.

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 implies when to use this tool: when accurate, npm-compatible semver evaluation is needed, as it uses 'the same semver engine npm uses' and is 'not a model guess'. However, it does not explicitly list alternative tools or state when not to use it, but with no sibling tools this is somewhat mitigated.

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