get_user_info

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

Annotations provide readOnlyHint=true, indicating safe read operation. The description adds context about the specific data retrieved (profiles, followers, verified status), but does not disclose additional behavioral traits like rate limits or authentication needs. With annotations present, the description adds minimal but acceptable context.

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 sentence of 9 words, efficiently conveying the purpose without extraneous information. It is perfectly concise and front-loaded.

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 tool has only one parameter, no output schema, and annotations present, the description is fairly complete. It adequately explains what the tool does, though it could mention return format or potential limitations. For a tool of this low complexity, it satisfies most informational needs.

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% for the single parameter 'userName' (described as 'Screen name (without @).'). The tool description adds no further information about this parameter, so it meets the baseline but does not exceed it.

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 'Get' and specifies the resource as 'Twitter user profiles, followers, verified status via API'. It distinguishes itself from sibling tools like get_account_info, get_user_info_by_id, and get_user_followers by listing specific data points it retrieves.

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 explicit guidance on when to use this tool versus alternatives. With many sibling get_user_* tools, the agent lacks criteria for selecting this one over others like get_user_about or get_user_followers.

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