OSINT MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool verifies email validity and deliverability, implying a read-only check, but does not disclose critical traits such as rate limits, authentication requirements, data sources (e.g., SMTP checks, DNS lookups), or what 'deliverable' entails (e.g., inbox existence vs. bounce detection). This is a significant gap for a tool with no annotation coverage.

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 appropriately sized and front-loaded: the first sentence states the core purpose, followed by a brief 'Args' section for the parameter. Every sentence earns its place with no wasted words, making it efficient and easy to parse for an AI agent.

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?

Given the tool's low complexity (1 parameter, no nested objects) and the presence of an output schema (which likely details return values), the description is minimally complete. However, it lacks behavioral context (e.g., rate limits, data sources) and usage guidelines, which are important for an OSINT tool with no annotations. The output schema may cover return values, but the description should still address operational aspects.

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 input schema has 1 parameter with 0% description coverage, and the description compensates by explaining the parameter: 'email: Email to verify.' This adds meaning beyond the schema's basic type definition, clarifying the parameter's role. Since there is only one parameter, the description adequately covers it, earning a baseline 4 for low parameter count and effective compensation.

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's purpose: 'Verify if an email address is valid and deliverable.' It specifies the verb 'verify' and the resource 'email address,' with additional qualifiers 'valid and deliverable' that add specificity. However, it does not explicitly differentiate from sibling tools like 'osint_email_finder' or 'osint_email_search,' which likely serve different purposes (e.g., finding emails vs. verifying them).

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 provides no guidance on when to use this tool versus alternatives. It lacks context such as prerequisites (e.g., needing an email address to verify), exclusions (e.g., not for bulk verification), or comparisons to sibling tools like 'osint_email_finder' (for finding emails) or 'osint_breach_check' (for checking breaches). This leaves the agent without clear usage instructions.

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