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

Annotations already declare read-only, open-world, idempotent and non-destructive, so the safety bar is covered. The description adds genuinely non-derivable behavior: severe-then-recent ordering, the limit/total plus per-type, per-severity and per-kind counts, what a warning record carries (issuer, onset_at, expires_at), what metadata holds, and the important containment caveat that a warning reaching into a country from outside is not listed. It stops short of describing truncation consequences or rate limits, which keeps it off 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?

Purpose, examples and alternatives are front-loaded in the first two sentences, with operational detail after. The final paragraph is dense — several distinct facts (sort order, limit, counts, warning fields, metadata, containment rule) packed into two long sentences — but almost every clause carries information an agent needs.

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 seven-parameter, optional-everything query tool with an output schema present, this is complete: location alternatives, filter defaults, ordering, limit behavior, and the geographic containment rule are all covered, and return-value shape is legitimately left to the output schema. An agent could call this correctly on the first attempt.

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; the description still earns above that by spelling out the mutual exclusivity and defaults of the location parameters ('give country, or bbox for a region, or neither for the whole world') and by framing the filters as narrowing from an all-inclusive default (every type, kind and severity included unless event_types, kinds, min_severity or days narrow it). That combination semantics is real value the schema does not state. It does not restate the antimeridian or range details, which the schema already handles.

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 opens with a specific resource set (wildfires, earthquakes, tsunami bulletins, cyclones, floods, volcanoes, droughts, official warnings, air quality) and an explicit scope (country, region, or world). It names the data sources and directly differentiates itself from get_hazards_near and get_country_profile, so an agent can tell the three apart without opening any schema.

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?

It states the selecting condition plainly — 'questions about an area rather than a point' — with concrete examples (Japan, European red warnings, strongest earthquakes this week). It then names both alternatives and their conditions: get_hazards_near for a point, get_country_profile for long-term risk. Nothing is left to inference.

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