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

Annotations already cover read-only, idempotent, non-destructive behavior. The description adds useful context that answers are stable facts from published pages with sources, and not minute-level availability or current closures. This clarifies output reliability without contradicting any annotation.

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 dense sentences front-load the core value ('Facts that do not change by the minute'), give usage examples, and name exclusions. Every clause earns its place; there is no filler.

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 two-parameter knowledge lookup with rich annotations, clear sibling routing, and no output schema, the description covers scope, examples, exclusions, and source character. An agent has everything needed to invoke it correctly.

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 schema already documents both parameters at 100% coverage, including the optional park name and the required free-form question. The description reinforces the kind of question expected with examples but does not add substantial semantic detail beyond the schema.

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 scope: stable facts like reservation policy, fees, pets, fires, facilities, and park descriptions from provider-published pages. It also explicitly contrasts itself with availability and closure tools, so an agent can distinguish it from siblings without opening their definitions.

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?

Gives concrete example queries ('does X allow dogs', 'how much is a site', 'when do reservations open') and explicit negative routing to parksopen_search_campsites and parksopen_check_alerts. This directly tells an agent when to pick this tool and when to pick a sibling.

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