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

Annotations already establish that this is a read-only, idempotent, non-destructive operation, so the description does not need to restate that. It adds useful scope context (multiple federal agencies and facility types), but no behavioral specifics such as result ordering, pagination, or data-source caveats.

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 tight sentences front-load the main purpose and then list filters and examples. There is no filler or repetition of schema details.

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 simple optional-parameter search tool with read-only annotations and fully described schema parameters, the description covers the resource scope, agency coverage, and filter options. Nothing critical is missing for an agent to decide whether and how to call it.

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 input schema already describes all four parameters, but the description adds value by naming the filter dimensions and giving concrete activity examples ('CAMPING', 'FISHING', 'HIKING') that the schema does not enumerate.

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 uses a specific verb ('Search'), a clear resource ('US federal recreation facilities'), and expands the scope with example facility types and agencies. It is clear enough to be distinguished from narrower siblings like recreation_search_campsites, though it does not explicitly name those alternatives.

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 states what the tool searches and the available filters (name, state, activity), giving clear context for when an agent would use it. It does not explicitly exclude alternatives such as recreation_search_recareas or recreation_facility_detail, so it falls just short of a 5.

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