Validate an email address — syntax, MX records, disposable/role detection, and typo suggestions. Keyless trial of the Email Validator API.
| Name | Required | Description | Default |
|---|---|---|---|
| Yes | The email address to validate. |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations provided, so the description carries the full burden. It lists validation checks but lacks details on return format, rate limits, or whether authentication is required. The mention of 'trial' hints at limitations but is insufficient for full transparency.
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 sentences, front-loaded with the verb and resource, no extraneous information. Every sentence adds value and is efficient.
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?
No output schema and no annotations; the description is adequate for a simple tool but could be more complete by mentioning return type or behavioral traits like asynchronous processing. Still, it covers the main purpose.
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 100% but the schema description is minimal ('The email address to validate'). The tool description adds context on validation aspects but does not elaborate on the parameter format or constraints beyond what the schema provides.
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 explicitly states it validates an email address and lists specific checks (syntax, MX records, disposable/role detection, typo suggestions). This clearly distinguishes it from sibling tools like currency_convert or ip_lookup which serve different purposes.
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 mentions 'Keyless trial' implying a trial context but does not explicitly state when to use this tool over alternatives or provide exclusions. Sibling tools are distinct in function, but no direct guidance is given.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct functionality (fetching URLs, converting currency, validating email, geolocating IPs, listing APIs, matching NAICS codes, fetching URL metadata), with no overlap in purpose.
All tool names follow a consistent verb_noun pattern in snake_case, e.g., currency_convert, ip_lookup, naics_match, ensuring predictability.
Seven tools is well-scoped for an API catalog service providing trial endpoints for a variety of utilities—neither too sparse nor overloaded.
The set covers key read-only operations for each featured API, though missing write or list operations (e.g., listing supported currencies) are minor gaps that users can work around.
