Piton de la Fournaise et séismes à La Réunion

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds substantive behavioral context beyond that: the earthquake window is explicitly 30 days, results can be broken down by day and by area (under the volcano vs. elsewhere on the island), and the source is OVPF-IPGP. It stops short of describing freshness/update cadence or the response shape, hence 4.

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?

One dense front-loaded sentence delivers the resource and its full content inventory, followed by a short intent-mapping clause. The enumeration is long but each item is a distinct returned field an agent would otherwise have to guess at, so it earns its space; slight trimming of the ORSEC parenthetical would tighten it.

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?

There is no output schema, so the description carries the burden of explaining return content — and it does, listing eruption status, ORSEC level, access conditions, publications, and earthquake coverage. It leaves unanswered only secondary details like update frequency and exact formatting for the per-day earthquake breakdown.

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 tool takes zero parameters, so the baseline is 4 and there is nothing for the description to compensate for. It correctly presents the tool as a parameter-free status query rather than suggesting any filtering options.

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 names a specific resource (Piton de la Fournaise volcano status and Réunion earthquakes) and enumerates the exact content returned: eruption status, ORSEC level, last eruption date, Enclos Fouqué access, OVPF publications, and the last 30 days of earthquakes. No sibling tool covers volcano or seismic data, so it is clearly distinguishable from the weather/water/traffic tools in the list.

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 closing clause maps concrete user intents to the tool ("le volcan est en éruption ?", "on peut monter au volcan ?", "il y a eu un séisme ?"), which is strong guidance for intent routing. It does not state exclusions or name alternatives, but no sibling overlaps this domain, so the gap is minor.

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