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

Annotations already declare readOnlyHint, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds genuinely useful behavior beyond that: with no filters it returns the full set sorted by descending AI connectivity, which tells the agent what to expect from a bare call. It does not cover pagination/limit truncation behavior.

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?

Three short sentences, no filler: the action and resource come first, the filterable fields second, and the default/ordering behavior last. Every sentence earns its place and the information 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?

With no output schema, the description usefully explains what a bare call returns (all devices ordered by AI connectivity), and annotations carry the safety profile. The only minor gap is that limit/pagination and the shape of returned records are not described, but for a 0-required-param search tool this is close to complete.

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 description coverage is 100%, so the schema already documents all five parameters and both enums. The description restates the filter semantics (partial match across product name/brand/summary, category, AI-rating floor, interface type) but adds little syntax or format detail beyond the schema, so the baseline of 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?

The description gives a specific verb (検索) and resource (ロボ図鑑の収録デバイス) and enumerates the four filter dimensions, so an agent immediately knows this is a filtered-list tool. It never explicitly names the sibling get_device to draw the single-vs-many boundary, but the resource scope makes the distinction reasonably inferable.

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?

It states a concrete default behavior ('条件を省くと全件をAI接続性の高い順に返す'), which tells the agent this works with zero filters and how results are ordered by default. However, there is no guidance on when to reach for this over get_device or list_guides, and no exclusions are given; usage is only implied.

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