terrain_profile

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so safety is covered. The description adds valuable behavioral details beyond annotations: it samples along a true geodesic, returns full profile plus statistics, and all samples come from one batched request rather than one call per point. This informs performance expectations and output nature. It does not contradict annotations. The only minor gap is lack of mention of any potential errors or limitations, but given the annotations and output schema, it's more than adequate.

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 concise, front-loaded with the primary purpose, and each sentence adds value. It starts with the core function, then explains the sampling behavior and statistics, and finally provides usage guidance and differentiation from a sibling. No filler or redundant content. It is well-structured and efficient.

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 tool with three parameters (fully covered by schema), strong annotations (read-only, idempotent, non-destructive), and an output schema, the description covers all essential aspects: what it does, how it behaves (true geodesic, batched), when to use it, and how it differs from the sibling. It leaves no critical gap for an agent to select and invoke it 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?

Schema description coverage is 100%, so the baseline is 3. The description does not add extra meaning to the parameters beyond what the schema already provides; it mentions 'samples' in the context of the tool's action but does not elaborate on the parameter format or constraints. The schema already defines origin, destination, and samples with clear descriptions and bounds. Therefore, a 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 verb ('Get'), a clear resource ('terrain elevation profile'), and the scope ('along a path between two points'). It explicitly differentiates from the sibling tool terrain_elevation by noting this tool samples the straight line between two ends, while the sibling handles single or scattered points. This is unambiguous and distinguishes it from all siblings.

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 provides explicit use cases ('cycling and hiking route difficulty, pipeline and cable routing, drainage assessment, or sizing earthworks') and directly names the alternative ('use terrain_elevation') for different scenarios ('single point, or at a scattered set of them'). This leaves no doubt about when to choose this tool over the sibling.

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