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

Annotations already indicate read-only, idempotent, and non-destructive behavior. The description adds useful behavioral context by specifying pagination support and the specific fields returned, complementing the annotation hints without contradiction.

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 description is extremely concise with two short sentences. The first sentence states the core purpose, and the second details return fields and pagination. No unnecessary information, front-loaded and efficient.

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 list tool with good schema coverage and existing annotations, the description covers the key aspects: what is returned, how pagination works, and the user scope. It is complete enough for an agent to use correctly, though it might optionally mention default ordering or rate limits.

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?

With 100% schema description coverage, the schema already explains both parameters. The description reinforces that username is without '@' and that cursor is for pagination, but adds no new meaning beyond what the schema provides.

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 clearly states the tool gets a paginated follower list for a Twitter/X user, specifying the verb 'Get' and the resource 'follower list'. It lists returned fields (username, display name, bio, follower count, verified status) and mentions pagination, distinguishing it from sibling tools like profile retrieval.

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 explicitly guide when to use this tool versus alternatives (e.g., twitter.users.profile for a single profile). It mentions cursor pagination, implying iterative usage, but lacks explicit context about when to use or avoid this tool.

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