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

The annotations only declare readOnlyHint and openWorldHint; the description adds material behavior an agent would not otherwise know: the dataset does not name the pathogen, results are capped at 50 sites per call, each successful call costs $0.002 in USDC via x402, and failed calls are not charged. These are non-obvious operational facts needed before committing to a paid call.

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?

Purpose, fields, limitation, cap, alternatives, and price are front-loaded in a compact block with no wasted sentences. The semicolon-heavy construction is dense and could be broken into shorter sentences, but every element earns its place.

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?

An output schema and annotations already exist, and the description supplies the remaining decision-critical context: data source, returned fields, the non-COVID caveat, the per-call cap, payment terms, and sibling routing. Nothing material is missing for a two-parameter paid query.

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 coverage is 100%, so 'state' and 'max' are already fully documented by the schema. The description reinforces the one-state scope and the 50-site ceiling but adds no format or syntax detail beyond that, making the baseline 3 appropriate.

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 resource and scope: CDC NWSS sampling sites in one US state, and lists the fields returned (plant, county, population served, detection proportion, percentile, sample dates). It also explicitly separates itself from the named mortality and FluView siblings, so an agent can distinguish it without opening schemas.

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?

Names two alternative tools and the exact need each serves, which gives strong routing guidance. The condition for using this tool is implied by its purpose rather than stated directly, and apart from the 'not confirmed COVID-19 activity' caveat there is no explicit when-not-to-use statement.

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