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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds genuine behavioral context beyond that: cursor-based pagination and reverse-chronological ordering. It does not mention rate limits, result caps, or per-page sizes, which keeps it short of a 5.

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?

The substantive content is six tight clauses, front-loaded with what/why before the disambiguation and prerequisite. The injected pricing block adds non-behavioral noise, but the author's own prose is efficient and well ordered.

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 need no explanation. Between the description (scope, ordering, pagination, ID format, prerequisites) and the annotations (read-only, idempotent, open-world), nothing an agent needs in order to call this correctly is missing.

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 coverage is 100%, so the baseline is 3, but the description adds real meaning the schema lacks: user_id must be numeric and not an @handle, plus a named resolution path. Pagination via cursor is also called out, aligning with the schema's cursor field.

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 precise verb+resource+scope ('List only the verified accounts following a given X user') and adds ordering semantics ('reverse chronological order'). It explicitly distinguishes itself from the sibling get_twitter_user_followers, so an agent can route without opening either schema.

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 an explicit use case ('gauge the quality rather than the size of an audience'), names the alternative for the full list (get_twitter_user_followers), and states a prerequisite (resolve the handle with get_twitter_user_info). All three when/how/what-before questions are answered.

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