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

No annotations are provided, so the description carries the full behavioral burden. It discloses the core behavior ('lightweight liveness response') and implies a safe, non-mutating read, but does not explicitly state idempotence, side-effect absence, auth requirements, or output format. For a liveness probe this is mostly sufficient, though not fully explicit.

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?

Three short sentences, front-loaded with purpose before exclusions. Every sentence earns its place: behavior, positive usage, and negative usage with named alternatives.

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 liveness tool, the description supplies purpose, usage boundaries, and alternatives. The only minor omission is a precise description of the response shape, but 'lightweight liveness response' is adequate given the tool's simplicity.

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?

There are zero parameters and the schema is an empty object, so there is no parameter semantics for the description to add. The baseline for a zero-parameter tool is 4.

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?

States a specific verb and resource ('Returns a lightweight liveness response') and scopes it to reachability testing. It explicitly distinguishes itself from sibling discovery, capability, and pricing tools by naming the alternatives.

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?

Tells the agent exactly when to call this tool (verify the endpoint is reachable) and when not to (discovery, capability listing, pricing), and names the three alternative tools. This is a complete routing instruction.

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