amiibo_types

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 covered structurally. The description adds only the concrete example values of the returned types; it says nothing about ordering, whether the list is exhaustive versus a fixed enum, or how the data behaves if Amiibo adds a new type, which the openWorldHint makes relevant.

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?

A single front-loaded sentence with the resource first and clarifying examples at the end; nothing is wasted. It is nearly minimal, though a short clause on what the values are useful for would have earned its place without bloat.

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 zero-parameter enumeration with a clean input schema, strong read-only annotations, and no output schema, the description is sufficient to call the tool correctly. The only missing piece is how this list relates to the sibling amiibo tools, which would help an agent chain calls.

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 tool takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate. The parenthetical examples are a small bonus but not parameter documentation.

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 states a specific verb and resource ('List all Amiibo product types') and names example values (figure, card, yarn), so an agent knows exactly what taxonomy is returned. It does not explicitly contrast itself with the sibling enumeration tools amiibo_search or amiibo_by_series, which keeps it just short of a 5.

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?

Usage is only implied: an agent can infer this is the tool to call when it needs the set of valid product-type values, but the description never says when to prefer it over amiibo_search or amiibo_by_series, nor whether the result is meant to feed a filter. No exclusions or prerequisites are given.

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