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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds only the data shape (Metascore + user score), which the output schema already carries, and says nothing about auth, rate limits, or slug resolution.

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 compact sentence with the resource front-loaded and no filler. It is appropriately sized, though it is arguably terse to the point of under-specification rather than being genuinely well-structured.

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 an output schema present, return values need no explanation, and the sole parameter is fully documented in the schema. However, the description omits how to find a valid slug and when to choose this detail tool over its review siblings, leaving a gap for a detail endpoint.

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?

There is a single required parameter and schema coverage is 100%, so the schema fully documents the slug format with examples. Per the baseline rule for high coverage, 3 is appropriate; the description adds no parameter meaning beyond the schema.

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 (Metacritic movie detail) and enumerates the payload (Metascore + user score), which implicitly separates it from the sibling review endpoints like metacritic_movie_critic_reviews. It stops short of explicitly naming those siblings, so an agent must infer 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?

There is no when-to-use guidance, no mention of when to prefer this over metacritic_movie_critic_reviews or metacritic_movie_user_reviews, and no hint about how to obtain the required slug (e.g. via metacritic_browse). Usage must be inferred from the name alone.

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