Gender from a username

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

With no annotations provided, the description carries the behavioral burden. It transparently discloses that the tool extracts a first name from the handle and then makes a gender prediction, which conveys that the result is probabilistic rather than authoritative. It does not describe edge cases like handles with no recognizable name, but the core behavior is clearly stated.

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, front-loaded sentence with no filler or repetition. Every word contributes to understanding the tool's core 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?

The tool has no output schema, and the description does not specify the exact return format or behavior for ambiguous or name-less usernames. The description is adequate for a simple prediction tool, but it leaves some operational details to the agent's inference.

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%, so the schema already fully documents both parameters, including the country weighting behavior. The description adds little beyond restating that the input is a username or handle, so the baseline score of 3 is appropriate.

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 uses a specific verb ('Extracts') and resource ('a username or social media handle'), and clearly states the outcome ('predicts its gender'). It distinguishes itself from siblings like gender_from_email and gender_from_name by explicitly targeting usernames and handles.

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 intended input context is implied by 'username or social media handle', which signals when to use this tool rather than gender_from_name or gender_from_email. However, no explicit guidance is given about when not to use it, nor are sibling alternatives named.

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