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

No annotations exist, so the description must carry the behavioral load; 'Get' signals a read-only operation and the field list hints at the response shape. It does not disclose error behavior when both optional keys are omitted, or whether id takes precedence over number.

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?

One front-loaded sentence that states the lookup keys first and the returned fields second, with no filler wording.

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, enumerating returned fields (title, date, summary, characters, arc, links) is genuinely useful. However, the unusual schema (zero required parameters, two alternative keys) is left unexplained, which is the main gap for an agent deciding how to call it.

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 schema already documents id, number, and locale. The description only adds that the id is a post id / X status id and that number is a manga episode number, which is largely duplicated from the schema; it adds no guidance on the id-vs-number precedence.

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 ('Get') and resource ('one episode') plus the two lookup keys (post id or manga episode number) and enumerates the returned fields. That clearly separates it from list-style siblings like search_episodes and latest_episodes, though no sibling is named explicitly.

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 implies the single-record lookup case by describing the two key types, but never states when to prefer this over search_episodes or latest_episodes, nor what to do if neither id nor number is supplied.

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