Set GDL parameters of elements

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

Adds substantial behavior beyond the annotations: changes occur in one undo step, the part's parameter script runs like the settings dialog, dependent parameters update, invalid values are corrected or rejected, and changing A/B resizes the element. It also discloses the return shape. This is far richer than the destructiveHint/idempotentHint flags alone.

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 the core action, then scope, then behavior, then param rules and return format. Dense but every clause carries information; slightly long but no filler.

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?

No output schema exists, yet the description supplies the return format (guid+parameters or error) and the failure mode for invalid values. Combined with 100% schema coverage and the get_gdl_parameters pointer, an agent has everything needed to call 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 coverage is 100%, so the baseline is 3; the description still adds the merge/precedence semantics ('per-element values win') and the 'Changing A/B also resizes' note, which the schema does not state. It reinforces rather than duplicates the schema's unit and name guidance.

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 ('Changes GDL parameters') and resource, and enumerates the element types it applies to (objects, lamps, doors, windows, skylights, zones, labels). This clearly separates it from siblings like modify_elements (geometry/properties) and get_gdl_parameters (read-only).

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?

Explains the two ways to supply values (per-element and top-level) and the precedence rule, and routes the agent to get_gdl_parameters for parameter names. It stops short of explicitly contrasting with modify_elements or modify_zones, so it lacks full 'when-not' guidance.

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