twitter_user_mentions

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

Annotations already declare readOnly, non-destructive, and open-world, so the safety profile is covered. The description adds real behavioral context beyond that: the to: operator search mechanism, the return contents (author info and metrics), and cursor pagination. It stops short of 5 because it doesn't note rate limits or result-cap quirks.

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?

Front-loaded with the core purpose, then mechanism, return shape, pagination, and use cases in four tight sentences with no filler. Every sentence carries distinct information.

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 read-only/open-world annotations and no output schema, the description is largely self-sufficient: it explains purpose, mechanism, returns, and pagination. It could add a note on the upstream page-size quirk already present in the schema, but nothing essential is missing for correct invocation.

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%, so all three parameters (username, count, cursor) are already fully documented in the schema, including the count advisory. The description only echoes pagination with cursor and adds no syntax or format detail beyond the schema. Baseline 3 applies.

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 (Get) and resource (recent public tweets mentioning a user) and clarifies the mechanism via the to: operator, which distinguishes it from a plain user-timeline tool. It does not explicitly name or contrast against the closest siblings like twitter_user_tweets or twitter_tweet_replies, so it stops short of a 5.

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?

Gives concrete when-to-use cases (monitor brand mentions, replies directed at an account, public conversations about a person). No when-not guidance or named alternative tool, so it lacks the routing/exclusion detail a 5 would need.

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