health

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

Annotations only declare readOnlyHint=true, so the description earns credit for disclosing that the probe 'does not contact instances' — a genuinely useful scope boundary that prevents misreading an all-healthy response as instance health. It stops short of describing what the response contains or failure semantics, which keeps it below 5.

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?

Two tight sentences: the capability first, then the routing to alternatives. Zero filler and no repetition of the name or endpoint twice.

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 no-arg, read-only liveness probe with rich annotation and full schema coverage, the description covers purpose, scope, and sibling routing. The only gap is the shape of the result (e.g. status payload or degraded state), which there is no output schema to cover.

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 tool takes zero parameters, so there is no parameter semantics to convey; the baseline for a no-param tool applies. Nothing in the description is needed to disambiguate arguments.

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 ('Read the API's own liveness probe') and anchors it to a concrete endpoint (GET /health). The scope qualifier 'its own' plus the sibling callouts make it unambiguously distinct from instances_ping_all and ping.

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 routes the agent: use instances_ping_all for instance reachability and diagnose for auth/version checks. Both alternatives are named with the condition that selects them, leaving nothing to inference.

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