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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable context beyond this: it is lightweight, requires no auth, and returns specific fields (server identity, deploy version, tool count, station coverage, update times) to confirm 'freshness, not just liveness'. This fully discloses behavior and return value scope.

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 two sentences, front-loaded with the key action ('call this first'), and every clause adds useful detail: what it returns, the no-auth/lightweight nature, and the distinction between liveness and freshness. No filler or redundancy.

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 zero-parameter, read-only health check, the description fully covers purpose, usage, and output expectations. It even notes the update times for realtime layers, which is more than necessary given the output schema exists. It is complete for an agent to decide when and how to invoke it.

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 has zero parameters, so there is nothing to describe beyond stating 'no arguments', which the description does. Baseline for 0 params is 4, and the description reinforces the schema. There is no missing parameter information.

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 opens with 'Connection test / health check' and specifies 'call this first to confirm the server is reachable', giving a specific verb and resource. It clearly distinguishes itself from sibling data-retrieval tools by focusing on server health and returning aggregated metadata rather than domain data.

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 instructs 'call this first' to confirm reachability, establishing it as the initial check before using other tools. It also mentions 'No auth, no arguments, lightweight', implying it is the low-cost entry point. The description makes the usage context clear without needing to name alternatives.

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