rate_media

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

The annotations already declare readOnlyHint=false and destructiveHint=false, so the mutating behavior is covered. The description adds the operational requirement PLEX_ENABLE_MUTATIVE_OPS=true, which is beyond the annotations and helpful. However, it does not disclose side effects such as whether the rating overwrites an existing one, and no contradiction with annotations 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, genuinely informative sentence that includes the core action and the critical prerequisite without filler. Every word earns its place, and the important operational condition is neatly parenthesized.

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 simple setter with only two fully-described parameters and no output schema, the description and schema together are sufficient. It captures the purpose, the operation type, and the necessary configuration flag. Missing only minor behavioral nuance like return values or confirmation, which is not essential here.

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%, and both parameters have clear descriptions (rating range 0 to 10, ratingKey as local Plex rating key). The description does not add further parameter meaning beyond the schema, so baseline 3 is appropriate.

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: 'Set the user's Plex rating for a media item.' This clearly identifies what the tool does. It also distinguishes itself from sibling tools like update_metadata or mark_watched, as none of those specifically target user ratings.

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 description does not state when to use this tool versus alternatives, nor does it mention any exclusions. It only includes a prerequisite environment variable, which is a technical requirement, not usage guidance. There is no comparison to sibling tools or conditions like 'use this when you need to change a rating.'

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