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

With no annotations provided, the description carries the full burden of explaining behavior, but it only communicates cost and payment method. It does not state what the tool returns, whether it is read-only, how pagination behaves, or what 'Light' means operationally.

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 short but front-loads redundant label-like text ('User Following / Light') and spends its most informative sentence on billing. It is not bloated, but it does not use its brevity to clarify the tool's actual purpose.

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?

The tool has no annotations and no output schema, yet the description omits the core operation, response shape, and any trade-offs versus the many sibling following/follower tools. The required-parameter situation is also ambiguous because the schema has no required fields despite stating exactly one of id/username is needed.

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 documents most parameters (75% coverage), including the id/username constraint and count limit. The description adds no parameter-level meaning beyond the schema, so it neither improves nor degrades the baseline.

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 mostly restates the title ('User Following / Light') and provides billing metadata rather than a clear verb-plus-resource statement. It does not say the tool retrieves the list of accounts a user follows, nor does it distinguish itself from siblings like get_v1_1_Followers or get_v2_Following.

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?

No guidance is given on when to use this tool versus alternatives such as get_v2_Following, get_v1_1_Followers, or get_email_search_by_username. The billing note is operational information, not usage context.

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