my_rating_stats

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

Annotations already declare readOnly, idempotent, non-destructive, and open-world, so the safety profile is covered. The description adds the useful behavioral detail that the scope is the configured user's entire history rather than a filtered subset, which the annotations do not convey. It does not discuss cost or response size for a potentially large history.

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 sentence front-loads what the tool returns, then enumerates the metrics in a compact colon list. Every clause adds content; nothing is redundant or padded.

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 parameters, an output schema present, and rich annotations, the description only needs to convey scope and the metric set — both are stated. An agent has everything required to call this correctly.

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 are zero parameters, so the baseline is 4. The description still earns its keep by clarifying that the user is 'configured' — i.e., the tool implicitly targets the authenticated user, which explains why no parameter is needed.

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 resource (aggregate statistics over the configured user's ratings history) and enumerates exactly which figures are computed (count, average, 1-10 spread, per-year, genres, decades, IMDb comparison). The aggregation framing implicitly separates it from listing siblings like my_ratings or my_rating_for, but 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?

Usage is only implied: the phrase 'whole ratings history' suggests when this aggregate view is appropriate rather than a per-title lookup. There is no explicit when-to-use/when-not, no mention of alternatives such as my_ratings.

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