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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds real behavioral context beyond that: it discloses the exact shape of the payload and that geometry is simplified to ~10 m and 5 decimal places, which tells the agent the outlines are lossy and unsuitable for precision work.

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?

Two tight sentences, with the resource and return fields front-loaded and the optional flag behavior second. Every clause carries information; nothing is padding.

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 usefully enumerates the returned columns and the geometry flag's effect, so an agent can plan around the result. Minor gaps remain: no default value for include_geometry and no pagination/volume expectations for workspaces with many zones.

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 only 50% — zone_id is documented as 'Only this zone' but include_geometry has no schema description. The description compensates by explaining what include_geometry actually does (adds each zone's outline as GeoJSON, simplified). Both parameters now have meaning, though no default behavior for include_geometry is stated.

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 verb (list) and resource (the workspace's service zones) and enumerates the returned fields, so an agent knows exactly what it gets back. It implicitly distinguishes itself from the location-scoped sibling zones_for_location by calling out the workspace-wide scope, but never names that sibling 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?

Usage is implied rather than stated: the include_geometry sentence tells you when to set that flag, but there is no guidance on when to prefer this tool over zones_for_location or other zone-related siblings, and no exclusions. Adequate but leaves routing to inference.

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