Zapmail MCP Server

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

No annotations are provided, so the description must fully disclose behavioral traits. It only states the action ('remove unused domains') without detailing permissions, side effects (e.g., irreversible deletion), rate limits, or response format. This is inadequate for a mutation tool with zero annotation coverage, risking misuse.

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 overly concise to the point of under-specification. The first sentence is redundant with the title, and the second ('Invoke this endpoint.') is filler that adds no value. It lacks front-loaded critical information, making it inefficient despite its brevity.

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 complexity of a mutation tool with 7 parameters, no annotations, and no output schema, the description is severely incomplete. It omits essential details like behavioral traits, usage context, and return values, failing to provide adequate guidance for safe and effective tool invocation.

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, documenting all 7 parameters (e.g., method, path, body). The description adds no parameter-specific meaning beyond the schema, so it meets the baseline of 3 where the schema does the heavy lifting, but fails to compensate with any additional context.

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 'This endpoint allows you to remove unused domains. Invoke this endpoint.' is tautological—it restates the tool name/title ('Remove unused domains') without adding specificity. It lacks a clear verb+resource distinction from siblings like 'delete_dns_records_14109023e0' or 'remove_mailboxes_instantly_19455787e0', failing to clarify what 'unused domains' means or the scope of removal.

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?

No guidance is provided on when to use this tool versus alternatives. With siblings like 'delete_dns_records_14109023e0' and 'remove_mailboxes_instantly_19455787e0', the description offers no context, prerequisites, or exclusions, leaving the agent without direction on appropriate usage scenarios.

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