Inxmail MCP

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

With no annotations provided, the description carries the full burden and successfully discloses key behavioral traits: return format ('HAL+JSON'), structure ('_links to all available resources'), and safety profile ('Read-only, no side effects'). Could improve by mentioning rate limits or authentication requirements.

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?

Four sentences efficiently structured: (1) core action, (2) return format/content, (3) usage context, (4) safety properties. Every sentence earns its place with zero redundancy or filler.

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?

Despite lacking an output schema, the description compensates by detailing the return structure (HAL+JSON with _links) and enumerating example resources. Adequate for a simple discovery endpoint, though rate limit or caching details would strengthen it further.

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 contains zero parameters. Per the baseline rule for zero-parameter tools, this earns a default score of 4. The description correctly omits parameter discussion as none exist.

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 specific action ('Get the Inxmail Commerce API entry point') and distinguishes this discovery/entry-point tool from its operational siblings (add_to_blacklist, check_email_blocked, etc.) by positioning it as the root resource for API exploration.

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?

Explicitly states when to use the tool: 'to discover available endpoints or verify API connectivity.' This provides clear context for an agent to invoke it before attempting specific resource operations, though it doesn't explicitly name alternative tools to avoid.

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