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

Annotations already declare readOnly/idempotent/no-destructive, so the lower bar is met with added context: legal basis, statutory thresholds, keyless access, and that results indicate current-year vs closed-archive provenance. Lacks detail on pagination or result ordering, so not a 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?

Front-loaded with the core purpose, then conditions, then the price-vs-list distinction and the California-only caveat. Dense but every sentence carries information; the legal citation and WAC gloss are borderline but justified for disambiguation.

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 still tells the agent what is returned (increase amount, post-increase WAC, current vs archive provenance) and sets scope/geography expectations. Nothing essential is missing for correct invocation.

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 the baseline is 3, and the description adds real value: it explains the year-omission behavior ('omit to search every year') and how drug/manufacturer matching works ('name/fragment'), beyond what the schema states.

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+resource: California manufacturer disclosures of a prescription drug's WAC increase. It defines WAC inline and implicitly separates itself from siblings like ca_rx_wac_five_year_history and ca_rx_new_drug_launches by scoping to 'increases' only.

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 says how to search (drug name/fragment, manufacturer, NDC), that year is optional and omitting it searches every year, and routes price-vs-payer questions to nadac_price/asp_payment_limit. Both when-to-use and alternatives are stated.

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