Zapmail MCP Server

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

No annotations are provided, so the description carries full burden. It states 'Add DNS Records' which implies a write/mutation operation, but doesn't disclose behavioral traits like required permissions, whether it's idempotent, rate limits, or what happens on failure (e.g., partial updates). The endpoint invocation note is generic and adds no behavioral context.

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 short sentences, but the second sentence ('Invoke this endpoint.') is redundant and wastes space. The first sentence is front-loaded with the core purpose, but overall structure is minimal without efficient use of words to convey necessary context beyond the obvious.

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?

For a mutation tool with 7 parameters, no annotations, and no output schema, the description is inadequate. It lacks details on required inputs, expected outcomes, error handling, and how it relates to other DNS tools. The context signals indicate complexity, but the description doesn't compensate, leaving significant gaps for an AI agent.

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 description coverage is 100%, so parameters are fully documented in the schema. The description adds no parameter-specific information beyond the generic 'for a given domain', which doesn't clarify how domain is specified (e.g., via pathParams or query). With high schema coverage, baseline 3 is appropriate as the description doesn't enhance parameter understanding.

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 states the action ('Add DNS Records') and resource ('for a given domain'), which is clear but vague. It doesn't specify what types of DNS records or how many, and doesn't differentiate from siblings like 'update_dns_records_13629370e0' or 'delete_dns_records_14109023e0'. The phrase 'Invoke this endpoint' is redundant and adds no purpose clarity.

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 on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., domain ownership), when not to use it, or refer to sibling tools like 'update_dns_records_13629370e0' for modifications or 'check_dns_records_13521093e0' for verification. The description provides only basic functional context.

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