search_username

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

No annotations provided, so description carries full burden. It describes the tool as passive, public-source collection using specific tools, but lacks details on process (e.g., concurrent queries, rate limits) or error handling.

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?

Two concise sentences: first covering purpose and method, second usage guidelines. No wasted words, front-loaded with key information.

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?

Covers purpose, method, and authorization, but lacks output details. Since no output schema exists, description should hint at result format or behavior when username not found, which it does not.

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 coverage is 50% with only json_output described. The description does not add meaning beyond the schema for either parameter; username lacks any format or constraint details. Minimal enrichment.

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 tool enumerates and verifies platforms where a username is registered, using specific sources (sherlock and WhatsMyName subset). It distinguishes from sibling tools focusing on other entities like domains or emails.

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?

Explicitly states authorized use only and passive nature. While it does not compare to sibling tools, it provides clear context for when to use (authorized assessment of own assets or authorized targets).

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