Get server info and connection status

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

The description goes beyond the annotations (readOnlyHint, idempotentHint, etc.) by explaining that the tool performs a live test call to verify credentials, that the test_connection parameter costs one request against the rate limit, and that the 'connection' field reports success. This adds operational context not present in structured fields.

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 compact and well-organized: a one-sentence purpose, a one-sentence usage trigger, and a clear return-field list. Every sentence earns its place without redundancy or fluff.

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 having no output schema, the description explicitly enumerates the return fields (server_version, api_base_url, writes_enabled, etc.) and explains the meaning of 'connection'. Combined with strong annotations and clear usage guidance, the tool is fully understood without additional context.

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 single parameter is fully documented in the input schema ('Make one lightweight API call to verify the credentials. Costs one request against your rate limit.'), so the description adds little beyond what the schema already provides. The schema coverage is 100%, so a baseline score of 3 is appropriate.

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 uses a specific verb ('report') and resource ('this MCP server's configuration and verify the easybill API credentials'), clearly distinguishing it from sibling tools that focus on listing or retrieving business objects. It explicitly states what the tool does, leaving no ambiguity.

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 second sentence provides explicit, actionable triggers: 'Call this when a write tool appears to be missing, when you get authentication errors, or when you hit rate limits.' This is direct when-to-use guidance tailored to common agent failure modes, and no alternatives are needed since the tool is unique.

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