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

Adds real behavioral context the annotations don't carry: ambiguous names are refused with candidate ids, and the tool accepts either a name or an id. However, annotations declare destructiveHint=true and idempotentHint=true, and the description never warns that an existing rating may be overwritten or that repeat calls are safe — the key mutation semantics are left to the annotations.

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?

Two tight sentences, front-loaded with the core action before the edge-case behavior and the sibling redirect. The phrase 'and its saved mark' is slightly compressed but no sentence 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?

An output schema exists, so return values needn't be described, and the ambiguity-refusal path is covered. The one missing piece is the destructive-overwrite warning for replacing an existing rating, which matters for a mutation tool flagged destructive.

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 86%, so the schema already explains type/year/saved/score/title/rating. The description restates the name-or-id input and the like/dislike/score choice without adding format or precedence detail (e.g. how rating and score interact), so it sits at the baseline.

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 and resource ('Set the user's rating of a title') and enumerates the accepted rating forms (like, dislike, score 1–10) plus the saved mark. It is clearly distinguishable from remove_rating and from lookup siblings like find_title.

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?

Explicitly routes removal to remove_rating and explains what happens when a name is ambiguous (refusal with candidate ids), which tells the agent how to recover. It stops short of stating when to prefer this over search_titles/find_title for disambiguation up front.

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