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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is fully covered without description help. The description adds what the result contains (slots plus recommended counters) but says nothing about data freshness — relevant for a rotation-based Rocket line-up dataset — or result size.

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?

Two short sentences with no filler: the first defines the resource and its contents, the second gives the one actionable parameter instruction. Front-loaded and every clause earns its place.

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 usefully characterizes the return shape (per-slot Pokémon and best counters), and the single optional parameter is handled. Minor residual gap: no mention of whether line-ups are time-limited/rotating, which matters for a Rocket-themed dataset.

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 baseline is 3, but the description goes beyond the schema by stating the default behavior when `key` is omitted (return every line-up), which the schema does not express. It stops short of explaining key format nuances beyond the schema's own 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 names a specific resource (Team GO Rocket line-ups) and enumerates scope in parentheses (Giovanni, leaders, typed grunts), plus what the payload contains (Pokémon per slot, best counters). It is clearly separable from siblings like raid_counters and max_counters by resource, though it never names a sibling to sharpen the boundary.

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?

'Omit `key` for every line-up' tells the agent how to get the full list, which is genuine usage guidance for the one optional parameter. However there is no explicit when-to-use-this-vs-siblings statement (e.g. raid_counters vs this for Rocket battles), so selection is left implied by the tool name.

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