Move objects so their lowest point sits at a specified height z; leave names empty to level all top-level objects. Use place_on instead when the floor is another object or not level.
Move objects (all top-level objects when names is empty) so their lowest point sits at height z. Use place_on instead when the floor is another object or not level.
| Name | Required | Description | Default |
|---|---|---|---|
| z | No | ||
| names | No |
Changes observed during successful MCP inspections.
v0.4.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so the description carries the full burden. It usefully discloses scope behavior (all top-level objects when names is empty), which is real behavioral context. However, it never states that this is a mutating operation, whether it is reversible, or how it interacts with grouped/child objects, leaving the safety profile implicit.
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 sentences, zero waste, with the core transformation front-loaded before the alternative-tool routing. Nothing redundant.
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 simple 2-parameter, no-output tool, the description covers purpose, scope default, and the sibling alternative. Remaining gaps (coordinate frame, effect on non-top-level objects) are minor.
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%, so the description must compensate, and it does: it explains that an empty names list means all top-level objects and defines z as the target height of the lowest point. This adds genuine meaning beyond the bare number/null schema, though the coordinate frame (world vs. parent) is unstated.
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 (move) and resource (objects) plus the exact transformation applied (lowest point at height z), and explicitly names the sibling tool it is not (place_on). An agent can distinguish it from place_on, move_to_contact, and transform_objects without opening schemas.
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?
Provides an explicit alternative and the selecting condition: 'Use place_on instead when the floor is another object or not level.' This is exactly the when-not guidance that routes the agent correctly.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.