Follow/unfollow a user

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

With annotations indicating a non-read-only, non-idempotent mutation, the description adds the login prerequisite and the toggle semantics (first call follows, second unfollows). This goes beyond the structured annotations and helps the agent predict the state-changing behavior.

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 short sentences deliver the essential info: login requirement, action, and repeat behavior. No filler or repetition, and it's front-loaded with the most critical constraint (login).

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 single-parameter mutation with an output schema present, the description covers all necessary context: auth requirement, precise action, and toggling idempotence. The parameter is fully documented in the schema, so nothing 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?

The input schema already provides a highly descriptive parameter note (numeric user ID, no username form, resolve via search_user/get_user_profile). Since schema coverage is 100%, the description doesn't need to add more, and it doesn't—this meets the baseline for schema-heavy documentation.

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 action ('Toggle following another AniList user') and the scope ('from the authenticated user's account'), which distinguishes it from sibling tools like toggle_favourite. The title also clarifies the follow/unfollow duality, reinforcing the purpose.

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?

It explicitly notes the login requirement and explains the toggling behavior ('Calling it again on the same user unfollows them'), which tells users when to use it and what to expect. It doesn't name alternatives, but no other sibling tool provides follow functionality, so the usage context is clear.

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