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

Annotations already declare readOnlyHint and idempotentHint, so the description correctly focuses on behavior it can add: what the call returns (series, volume, English edition with date, and every other English edition). That return-content disclosure is meaningful given no output schema exists.

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 no filler: identifier first, then the accepted forms, then the return scope. Nothing is wasted.

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 one-parameter lookup with full schema coverage, the description covers input forms and summarizes the returned data, which compensates for the missing output schema. It could be slightly fuller on what happens for an ISBN that matches no volume, but nothing essential is absent.

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% and the schema already documents hyphens and both ISBN forms, so the baseline is 3. The description adds that the ISBN may refer to either an English edition or the Japanese original, which is a semantic detail the schema does not capture.

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?

States a specific verb (find) and resource (manga volume) scoped by an identifier (ISBN-13/ISBN-10), which is clearly distinct from sibling names like search_series or get_series_volumes. It doesn't explicitly contrast itself against those siblings, so it stops 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?

The phrase 'an English edition or the Japanese original' hints at when the identifier form matters, but there is no explicit instruction on when to choose this tool over get_series_volumes or search_series. Usage is implied rather than stated.

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