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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world. The description adds useful disclosure beyond that: the exact response payload (pong, uid, tenant, auth method) and the 'No PHI' assertion, which is material in a healthcare-adjacent toolset. 'No side effects' is somewhat redundant with destructiveHint=false/idempotentHint=true.

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 the tool's identity, then its return value, then its safety profile. Every sentence carries information an agent would want; nothing is padded.

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?

No output schema exists, and the description compensates by enumerating what comes back. With annotations covering safety semantics and no parameters to explain, an agent has everything needed to call and interpret this tool.

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?

Zero parameters, so there is nothing to document and the baseline of 4 applies. The schema is a closed empty object and the description correctly implies no inputs are needed.

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: a smoke-test tool that returns 'pong' plus caller identity fields. This is instantly distinguishable from every sibling, which all operate on care data (inbox, family members, providers), so an agent can route to it without opening the schema.

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?

'Smoke-test tool' makes the intended use case clear: verifying connectivity and auth. There is no explicit when-not guidance or named alternative, but no competing tool occupies this niche, so the implied usage is sufficient. It falls short of a 5 only because it doesn't say what a healthy vs. unhealthy result looks like.

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