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 retrieving metrics but doesn't disclose behavioral traits such as whether this requires specific permissions, if it's read-only (implied by 'retrieve'), rate limits, data freshness, or error handling. This is a significant gap for a tool that likely accesses system data.

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 front-loads the purpose. It avoids unnecessary words and directly states the key components (system metrics with examples). However, it could be slightly more structured by explicitly listing all metric types or adding a brief context sentence.

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 and no output schema, the description is incomplete. It doesn't explain what the return values look like (e.g., format, structure), any prerequisites, or behavioral aspects like latency or data scope. For a tool retrieving system metrics, this leaves critical gaps for an AI agent to use it effectively.

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 the three boolean parameters (includeCache, includeTimers, includeCounters) with descriptions and defaults. The description adds no additional parameter semantics beyond implying the types of metrics retrieved, which aligns with but doesn't expand on the schema.

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 verb 'Retrieve' and the resource 'system metrics', specifying types like API call statistics, cache performance, and error rates. It distinguishes from many sibling tools (e.g., get_server_info, health_check) by focusing on performance data, but doesn't explicitly differentiate from all potential overlaps like get_overall_report, which might include similar metrics.

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. For example, it doesn't mention if this is for real-time monitoring, historical analysis, or how it compares to sibling tools like get_overall_report or health_check. The description only states what it does, not when it's appropriate.

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