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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered; the description adds genuine behavioral context by describing the four-valued verdict per check (applies / does_not_apply / possible_check_required / unknown), the I/II/III category, permission_needed, and a per-check receipt. The 'Reference only' caveat and DIPS escalation rule set expectations about reliability, which is valuable for an agent acting on the output.

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 as a single interrogative sentence that frames the tool's purpose, followed by the return shape and two short caveats. The parenthetical check list is dense but each item carries information about coverage; nothing is wasted.

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 17-parameter, open-world lookup with a full output schema and read-only annotations, the description supplies what the structured fields cannot: the enumerated rule checks, the four verdict values, the category/permission outputs, and the advisory-only limitation. An agent has enough to call it correctly and interpret the response.

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 all 17 parameters (including defaults such as 'Omitted = reported unknown' and the JST offset convention) are already documented in the schema. The description only gestures at the inputs via 'this point, time and height' and the check list, adding little beyond the structured fields; baseline 3 applies.

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 question the tool answers — which Japanese drone rules apply at a given point, time and height — and enumerates the concrete checks returned (DID 2020, 150 m, night, airport screening, Small UAS Act facilities, MLIT emergency airspace, flight methods, 25 kg). This is clearly distinguishable from siblings like drone_rule_table (static table) and get_receipt (receipt lookup).

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 explicit framing ('Reference only') and a fallback for uncertainty ('uncertain = check DIPS'), plus a negative scope ('no applications prepared'), which tells the agent this is advisory, not a filing tool. It does not, however, name the sibling drone_rule_table or state when to prefer that over this one.

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