Place lamps

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

Annotations already declare the safety profile (not read-only, not destructive, not idempotent), and the description adds real value on top: the operation is 'in one undo step' (atomicity) and returns '[{guid, type} | {error}]' (return/error shape). These behavioral facts are not derivable from the annotations, though permission/context requirements are unaddressed.

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?

Front-loaded with purpose, then extra fields, then the name-lookup pointer, a usage tip, and the return shape. Every sentence carries distinct information with no padding, and the ordering matches how an agent would build the call.

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 non-idempotent mutation tool with no output schema, the description supplies the return shape, undo atomicity, the library-part lookup path, and the cross-reference to create_objects. It is close to complete; only authorization/precondition context is absent.

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 baseline is 3; the description still adds meaning by framing the parameter set as 'same fields as create_objects plus lightOn, lightColor {red, green, blue} (0..1) and lightIntensity', orienting the agent to the inherited-vs-new fields. The lightColor range and the elevation formula reinforce rather than merely restate the schema.

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 (Places) and resource (lamps), then defines lamps precisely as 'light-emitting GDL library parts of type Lamp' with examples. It explicitly distinguishes itself from the sibling create_objects by naming the extra light fields, so an agent can tell them apart without opening either schema.

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?

Gives concrete routing guidance: find names with search_library_parts {type: 'Lamp'}, notes names are localized, and supplies a practical elevation heuristic for ceiling lights. It does not explicitly state when to prefer this over generic create_objects, so it falls just short of full when/when-not coverage.

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