Check if a username is taken across 20+ platforms like GitHub, Twitter, Instagram, and npm at once, returning available, taken, or unknown status per site.
Check username availability across 20+ platforms simultaneously — GitHub, Twitter, Instagram, npm, and more. Returns taken/available/unknown status per platform.
| Name | Required | Description | Default |
|---|---|---|---|
| username | Yes |
Changes observed during successful MCP inspections.
v1.1.61Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It does disclose useful behavior: multi-platform fan-out and a tri-state 'taken/available/unknown' result, where 'unknown' usefully signals partial failure or blocked lookups. However it omits rate limits, latency expectations, and whether the check is cached or real-time.
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 tight sentences with zero waste. The multi-platform scope and the return shape are both front-loaded, so an agent gets the essential facts in a single read.
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?
With no output schema, no annotations, and 0% param coverage, the description should carry more. It covers purpose and the return vocabulary well, but leaves the input format and operational caveats (rate limits, unknowns, coverage list) unspecified.
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 single 'username' parameter has 0% schema description coverage, so the description is the only source of guidance. It implies a bare handle string but never states format constraints (no '@' prefix, no URL, case sensitivity), leaving a real gap for a 1-param tool with no schema docs.
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?
States a specific verb+resource ('Check username availability') with explicit scope ('across 20+ platforms simultaneously') and names representative platforms. It distinguishes itself from the domain-oriented siblings like netintel_domain_availability and netintel_name_gen.
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?
Usage is implied rather than stated — an agent can infer this is for pre-registration handle screening. There is no explicit when/when-not guidance and no mention of near-neighbor tools such as netintel_domain_availability or netintel_email_verify that an agent might confuse it with.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.