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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely non-derivable context: the value is expressed in metres above today's high-tide level, and the provenance (CCRS V3 2024, Ng et al. 2025, IPCC AR6) signals a sourced, region-locked projection rather than live observation.

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 front-loaded sentence with zero filler. The units and provenance are packed into the same sentence without a separate preamble, and every clause carries information the 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?

With no output schema, the description correctly carries the burden of stating what the returned number means (metres above today's high-tide level) and its source. It stops short of explaining how storm_surge alters the result or the valid year range, but those are documented in the schema.

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 schema already documents year, scenario, storm_surge, and lang with enums. The description's phrase 'a year and an emissions scenario' restates the schema rather than adding syntax or constraints, 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?

States a specific resource (projected sea-level rise at Singapore) with explicit scope (a year and an emissions scenario), units, and data provenance. An agent knows exactly what the tool returns, though it never names or distinguishes itself from sibling tools like flood_impact or when_does_it_flood.

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 when-to-use guidance, no exclusions, and no reference to the overlapping siblings (flood_impact, places_underwater, when_does_it_flood) that an agent might otherwise confuse with a sea-level projection query. Usage must be inferred entirely from the resource name.

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