Unosend MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool retrieves details and DNS records, implying a read-only operation, but doesn't cover critical aspects like authentication requirements, rate limits, error handling, or what specific details are included (e.g., ownership, expiration). For a tool with zero annotation coverage, this is a significant gap in 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?

The description is a single, efficient sentence that directly states the tool's purpose without unnecessary words. It's front-loaded with the core action and resource, making it easy to parse. Every part of the sentence earns its place by conveying essential 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?

Given the tool's complexity (a read operation with one parameter) and the lack of annotations and output schema, the description is minimally adequate. It specifies what the tool does but doesn't cover behavioral traits, usage context, or return values. For a tool with no output schema, the description should ideally hint at what 'details and DNS records' include, but it doesn't, leaving gaps in completeness.

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 100% description coverage, with the 'id' parameter documented as 'The domain ID'. The description doesn't add any meaning beyond this, such as explaining the format of the ID or where to obtain it. Given the high schema coverage, the baseline score of 3 is appropriate, as the schema does the heavy lifting for parameter documentation.

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 action ('Get details and DNS records') and the resource ('for a specific domain'), making the purpose understandable. However, it doesn't explicitly differentiate from sibling tools like 'list_domains' or 'get_email', which would require more specific context about what distinguishes this domain lookup from other domain-related operations.

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 doesn't mention prerequisites (e.g., needing a domain ID), exclusions, or comparisons to siblings like 'list_domains' (which might list domains without details) or 'validate_email' (which could involve domain checks). This leaves the agent to infer usage from the tool name alone.

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