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

No annotations are provided, so the description carries full burden. It discloses that each side is unioned first, the return format (JSON with ok, op, geojson), and that an empty geojson indicates no overlap, not an error. It lacks mention of side effects or authorization needs, but for a read-like analysis tool, the behavior is well-explained.

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 three sentences long, each adding value: purpose, operation details, and return format. It is front-loaded with the core action and very concise, with no wasted words.

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 presence of an output schema (not shown but indicated), the description sufficiently covers return values and edge cases. Parameter explanations are clear, and the sibling context shows this is a geometric overlay tool among many others, so the description is complete for its complexity.

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 0% (no parameter descriptions), so the description must compensate. It explains the 'op' parameter with its four allowed values and default, and implies that geojson_a and geojson_b are the two input FeatureCollections. This adds significant meaning beyond the schema's bare titles and types.

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 the tool's purpose: 'Combine two GeoJSON FeatureCollections with a boolean set operation.' It lists the operations (intersection, difference, symmetric_difference, union) and explains the behavior (each side unioned first). This distinguishes it from sibling tools like buffer_geojson, dissolve_geojson, and spatial_join_geojson, which handle different geometric operations.

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 implies use for boolean operations on geometries but does not explicitly state when to use this tool versus alternatives like buffer_geojson or dissolve_geojson. No clear context for when-not-to-use or specific prerequisites are provided.

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