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

Annotations already declare this a read-only, closed-world query, so the safety profile is covered. The description usefully discloses the output behavior (a year per scenario, capped at 'beyond 2150'), but says nothing about what 'scenario' refers to or the range/assumptions behind the projection.

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?

A single tight sentence with no filler, and the operative concept (year vs. 'beyond 2150') is front-loaded. It reads as a returned-value fragment rather than a full sentence, but no words are 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?

With no output schema, the description does the work of explaining the return value, which it handles adequately. However, 'each scenario' is never defined, so an agent cannot fully predict the response shape for a 2-parameter tool.

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 both parameters and the enum are already documented; the schema even carries the 0-9 bound. The description restates the rise_m meaning ('metres above today's high tide') but adds no syntax or constraint beyond the schema, so the 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?

The description names the resource clearly (year at which a scenario reaches a given sea-level rise) and pins down the return semantics, including the 'beyond 2150' sentinel. It implicitly distinguishes itself from siblings like sea_level and flood_impact, though it never says so explicitly.

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?

There is no statement of when to use this tool versus sea_level, flood_impact, places_underwater, or the other siblings. The agent must infer usage from the return-value phrasing alone.

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