follow_user

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

With no annotations, the description carries the full behavioral burden and provides almost nothing: it does not say this is a mutating write with side effects (target notification, follower count changes), whether it is idempotent, or what happens on unknown/suspended usernames. Only the basic mutation is implied by the verb "Follow".

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?

One short, front-loaded sentence with no wasted wording. It is efficient, though its brevity reflects under-specification rather than deliberate economy.

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 one-parameter tool with a fully documented schema, the description is enough to invoke it correctly. However, with no annotations and no output schema, the missing behavioral detail (idempotency, error cases, side effects) leaves a meaningful gap for a write operation.

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% and there is a single required parameter whose meaning ("Twitter username to follow") is fully documented in the schema. The description adds nothing beyond that, so the baseline of 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?

The description states a specific verb and resource ("Follow a Twitter user"), so the action is unambiguous. It does not acknowledge the inverse sibling unfollow_user or otherwise differentiate itself, but the intent is clear from the name plus phrase.

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?

There is no guidance on when to use this versus unfollow_user, no preconditions such as requiring an authenticated account, and no mention of cases where following is inappropriate (self, already-followed, suspended accounts). The agent must infer everything about applicability.

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