Marée à La Réunion

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

Beyond the annotations (readOnly, idempotent, openWorld), the description adds significant context: data is measured every minute by SHOM gauges at two locations, the next tides are computed by rundata from those measurements (not the official SHOM prediction), with stated accuracy (~15–20 min, 5 cm). This is exactly the kind of behavioral detail an agent needs.

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?

The description is front-loaded with the key purpose and includes a useful English translation. It is slightly lengthy due to bilingual repetition, but every sentence (source, outputs, computation caveat, accuracy, examples) earns its place.

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?

With no output schema, the description fully covers the return values (current level, tide direction, last observed high/low, next computed high/low) and adds data source and accuracy. An agent has everything needed to invoke the tool 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 input schema has 100% description coverage for the single optional parameter 'lieu', including examples and the empty-value behavior. The description does not add any new parameter semantics beyond what the schema provides, so the baseline score of 3 is appropriate.

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 states a specific resource (sea level from SHOM tide gauges) and a clear set of outputs (current level, tide direction, last/next high and low tides). It distinguishes itself from sibling weather tools by focusing on tides and explicitly notes the computed nature of the predictions.

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 gives concrete example queries (e.g., 'la marée monte ?', 'c'est quand la marée basse demain ?') that clearly indicate when to use the tool. However, it does not explicitly state when not to use it or name alternative tools, though no direct tide alternative exists among siblings.

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