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

Annotations already declare readOnly, openWorld, idempotent, and non-destructive. The description adds valuable behavioral context beyond those hints: 'No auth required; fair-use free API,' the flavor text source ('English, from most recent main game'), and the gender ratio encoding. This helps agents set expectations about authentication and data provenance without contradicting the annotations.

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 information-dense but not bloated. It front-loads the core purpose and field list, then adds three short clarifications (flavor text source, gender rate encoding, examples) and a brief auth/source note. Each sentence contributes value, though the long field list could be slightly more scannable.

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 an output schema exists, the description does not need to explain return values. It covers the tool's scope, key field meanings, parameter examples, and auth requirements. It is adequate for a simple single-parameter lookup with rich annotations, though it could mention potential edge cases (e.g., missing flavor text for some species) but that is minor.

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 input schema covers 100% of the parameter semantics, including a clear description of name_or_id and the caveat about base species names. The description adds only examples ('pikachu', 'eevee', etc.), which are redundant with the schema's examples and provide little new meaning. Baseline 3 is appropriate when the schema does the heavy lifting.

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 uses a specific verb ('Get') and resource ('species-level information for any Pokemon'), then enumerates the exact fields returned (flavor text, genus, generation, growth rate, etc.). The phrase 'species-level' differentiates it from the sibling pokeapi.pokemon.detail, which covers individual Pokemon data, so an agent can distinguish them without opening schemas.

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 clearly states it is for species-level information, which implies when to use it, but it does not explicitly name alternatives or state when not to use it. For instance, it doesn't say 'for individual Pokemon stats, use pokeapi.pokemon.detail instead.' The context is clear but exclusions are absent.

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