Validate and verify email addresses for deliverability, format compliance, and mailbox existence. Returns pass/fail status per email, syntax errors, domain validity, and SMTP verification result. Use before sending bulk emails to prevent bounces and protect sender reputation.
| Name | Required | Description | Default |
|---|---|---|---|
| emails | Yes | Array of email addresses to validate for syntax, domain, and deliverability |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations (readOnlyHint: true, openWorldHint: true) already cover the safety profile, and the description adds concrete behavioral context by listing what the tool checks (syntax, domain validity, SMTP verification) and what it returns (pass/fail status, errors, verification result). This goes beyond the annotations without contradicting them.
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 action and resource, followed by return summary and usage note. Every clause earns its place; no filler or repetition of schema details.
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, the description compensates by summarizing the return fields (pass/fail, syntax errors, domain validity, SMTP result) and the intended use case. Complexity is low (single array parameter), and the annotations cover safety. Missing minor details like rate limits or batch size, but the tool is sufficiently specified.
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%: the only parameter 'emails' is fully described as an array of email strings with examples. The description reinforces that validation happens 'per email' but does not add new syntax or format details beyond what the schema already states. Per the rubric, the baseline is 3 when schema coverage is high.
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 opens with a specific verb ('Validate and verify') and resource ('email addresses'), then details the scope: 'deliverability, format compliance, and mailbox existence.' This clearly distinguishes it from sibling tools (generate_leads, search_local_businesses) which focus on finding prospects, not validating existing addresses.
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 explicitly states when to use: 'Use before sending bulk emails to prevent bounces and protect sender reputation.' It gives a clear context but does not explicitly mention alternatives or when not to use it, such as for lead generation or address discovery.
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.
The two maps-related tools have slightly overlapping data (both return business name, address, phone, etc.) but distinct purposes: one for lead generation, one for general search. The email validation tool is completely different, so overall ambiguity is low.
All tool names follow a consistent verb_noun pattern in snake_case (generate_leads, search_local_businesses, validate_emails), creating a predictable naming convention.
Three tools are too few for a comprehensive Google Maps server. Critical features like geocoding, directions, place details, and reviews are missing, and one tool (validate_emails) is unrelated.
The tool set lacks essential Google Maps operations such as geocoding, directions, and detailed place information. The inclusion of an email validation tool further undermines domain completeness.