Zapmail 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. It mentions exporting to third-party applications or CSV, but doesn't disclose critical behavioral traits: whether this is a read-only or destructive operation, authentication requirements, rate limits, output format details, or side effects. The phrase 'Invoke this endpoint' adds no value. For a tool with potential data export implications, this lack of transparency is a significant gap.

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 brief with two sentences, but the second sentence ('Invoke this endpoint.') is redundant and adds no value. The first sentence is front-loaded with the core purpose, but overall structure is minimal without efficient elaboration. It's concise but under-specified, not optimally structured for clarity.

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 no annotations, no output schema, and 7 parameters, the description is incomplete. It doesn't cover behavioral aspects, usage context, or output expectations. For a tool that likely involves data export with multiple configurable parameters, this description leaves too many gaps for effective agent use, failing to compensate for the lack of structured metadata.

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 the schema fully documents all 7 parameters (e.g., method, path, body). The description adds no parameter-specific information beyond the general export purpose. It doesn't explain how parameters like 'method' or 'serviceProvider' relate to the export functionality. Baseline is 3 since the schema does the heavy lifting, but the description fails to add meaningful semantic 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 states the tool exports mailboxes to third-party applications or as CSV files, which provides a general purpose. However, it's vague about the specific mechanism (e.g., what 'export' entails operationally) and doesn't differentiate from sibling tools like 'get_export_info' or 'get_export_scenario', which might be related. It uses the verb 'export' with the resource 'mailboxes', but lacks specificity on scope or process.

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, context (e.g., after retrieving mailboxes), or exclusions. With many sibling tools like 'retrieve_all_mailboxes' and 'search_mailboxes', there's no indication of how this export tool fits into a workflow or when it's appropriate compared to other export-related tools.

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