x-mcp

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions listing followers but does not cover critical aspects like pagination behavior (implied by 'next_token' in schema but not explained), rate limits, authentication needs, or error handling. This leaves significant gaps in understanding how the tool operates beyond basic functionality.

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 a single, direct sentence that efficiently conveys the core action without unnecessary words. It is front-loaded with the main purpose, making it easy to parse quickly, and every part of the sentence contributes to understanding the tool's function.

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?

Given the complexity of a tool with 3 parameters, no annotations, and no output schema, the description is insufficient. It lacks details on return values (e.g., format of follower data), error cases, or behavioral traits like pagination. For a data retrieval tool in a social media context, more context is needed to ensure proper usage by an AI agent.

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 schema description coverage is 100%, with clear descriptions for all parameters (user_id, max_results, next_token). The description adds minimal value by mentioning 'numeric user ID', which is already covered in the schema. Since the schema does the heavy lifting, the baseline score of 3 is appropriate, as the description does not significantly enhance parameter understanding.

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 verb ('List') and resource ('followers of a user'), making the purpose specific and understandable. However, it does not explicitly differentiate from sibling tools like 'get_following' or 'get_user', which might also involve user-related data retrieval, leaving room for ambiguity in tool selection.

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 provides no guidance on when to use this tool versus alternatives, such as 'get_following' (which might list users followed by a user) or 'get_user' (which might retrieve user details). It lacks context on prerequisites, exclusions, or comparisons with siblings, offering minimal usage direction.

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