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

Beyond the readOnly/idempotent annotations, the description discloses important behavior: it returns a qualitative level plus direction and metadata, not raw counts, and explicitly states it is not medical advice. It also specifies how to handle a stale result, telling the agent to say so instead of reporting the level as current.

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 front-loaded: the first sentence states the core purpose, the second bounds expectations, and the third gives actionable stale-data handling. Every sentence earns its place without 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?

With no output schema, the description carries the burden of explaining the return payload, and it does so by mentioning qualitative level, direction, reported week, data date, age, and source. It also covers the stale signal and the important non-medical-advice caveat, making the tool sufficiently self-contained.

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?

Schema description coverage is 100%, so the schema already fully documents both parameters. The description adds no parameter-level detail, but none is needed because the enum descriptions and default value are already explicit.

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 names a specific verb and resource ('Return the current respiratory illness activity'), enumerates the illnesses covered (influenza, COVID-19, RSV), and scopes it to one country. It also clarifies what it does not return, which distinguishes it from sibling tools like list_outbreaks.

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 description gives clear context: this is for country-level qualitative activity with no incidence numbers, case counts, or personal risk assessment. It does not explicitly name alternatives, but the scoping and exclusions make the appropriate use case evident.

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