Relocate a rectangular area inside a cel to a new position, clearing the original pixels.
Move a rectangular region within a cel, clearing its source.
| Name | Required | Description | Default |
|---|---|---|---|
| x | Yes | ||
| y | Yes | ||
| width | Yes | ||
| dest_x | Yes | ||
| dest_y | Yes | ||
| height | Yes | ||
| filename | Yes | ||
| layer_name | Yes | ||
| frame_index | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It does reveal the crucial side effect of clearing the source, which is helpful, but it doesn't state what happens on overlap, whether clipping occurs, coordinate conventions, or any constraints on the destination. For a mutation tool, this is a significant gap.
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 a single sentence, which is concise, but it's under-specified for a tool with 9 required parameters. The brevity comes at the expense of essential information, so it's not appropriate sizing; it reads as a stub rather than a complete guide.
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 complexity (9 parameters, no output schema, no annotations), the description is grossly incomplete. It doesn't explain coordinate systems, overlap behavior, whether the source is cleared before or after the move, error conditions, or any constraints. An agent would have to guess about critical operational details, making this definition inadequate for reliable invocation.
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 0%, so the description must compensate by explaining parameter meaning. However, it provides no information about how x, y, width, height, dest_x, dest_y, or other parameters define the region or destination. It merely mentions a 'rectangular region' without connecting to any parameters. This leaves the agent with no understanding of the parameter semantics beyond the schema's type definitions.
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 action: 'Move a rectangular region within a cel' and adds the key effect 'clearing its source'. This distinguishes it from copy_region (which would not clear) and set_cel_position (which moves whole cels, not regions). The verb and resource are specific, though it doesn't explicitly name alternative tools.
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?
No guidance on when to use this tool versus alternatives like copy_region, erase_region, or set_cel_position. It doesn't mention scenarios where moving is preferred over copying, nor does it state prerequisites like needing a cel to exist. The usage context is implied by the name and description but not explicitly articulated.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.