Measure Area

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description does not need to restate safety. The description adds that it uses the shoelace formula, which implies the polygon must be simple and vertices must be ordered, providing useful behavioral context beyond the annotations.

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 a single sentence that directly states the tool's purpose and method. No unnecessary words or repetition. Front-loaded 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?

Given the tool's low complexity, full schema coverage, existence of an output schema, and clear annotations, the description is complete. It explains what the tool does, how it works (shoelace), and the input. No gaps remain for an agent to select and use 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?

With 100% schema coverage, the baseline is 3. The description adds 'using the shoelace formula' which hints at vertex ordering but does not specify format beyond what the schema already describes for the 'points' parameter. Minimal additional semantics.

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 clearly states it calculates the area of a polygon defined by vertices using the shoelace formula. This distinguishes it from sibling tools like analysis_measure_distance (length) and analysis_bounding_box (bounding area). The verb 'calculate' and resource 'area of a polygon' are specific.

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 description does not explicitly state when to use this tool versus alternatives like analysis_bounding_box. However, the name and description imply it is for polygon area, which is reasonably clear. Lacks explicit 'when not to use' or alternative suggestions.

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