Look up a Pokémon (Pokémon Champions)

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

With no annotations, the description takes on the full burden. It discloses the data source (Champions Pokédex/Serebii), the @smogon/calc fallback, the 'source' field to indicate which source was used, and the accuracy advantage for Mega evolutions. This goes beyond a bare 'lookup' and provides meaningful behavioral context, though it doesn't mention error cases or rate limits.

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 but packs in the main lookup purpose, return fields, an example of Mega naming, a data-source note, the source field, and the optional regulation behavior. Every sentence carries meaning, and it is front-loaded with the primary action.

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?

For a lookup tool with no output schema, the description explains the key return values (stats, typing, abilities, weight, moves, source) and the optional legality data. It covers the main use cases and edge cases of Mega forms. It does not describe the exact structure of the output, but the list of fields is sufficient for an agent to understand what to expect.

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 coverage is 100%, so the baseline is 3. The description adds value by clarifying accepted naming variants for Mega forms ('Staraptor-Mega' or 'Mega Staraptor'), and explaining that the optional regulation parameter checks legality and legal moves. This goes beyond the schema's terse examples.

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: 'Look up a Pokémon by name,' then enumerates the returned data (base stats, typing, abilities, weight, movelist, source). It also clarifies the tool's unique scope (Champions Pokédex, Mega forms) and distinguishes it from potential siblings by mentioning the source field and optional legality check.

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 usage for basic Pokémon lookups and emphasizes Mega evolution accuracy, but does not explicitly compare to sibling tools like check_legality or list_legal_moves. It mentions an optional regulation id for legality, yet doesn't state when to prefer dedicated legality tools. Context is present but exclusions/alternatives are not explicitly addressed.

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