copy_cel

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

Annotations declare this is a write operation (readOnlyHint=false) that is non-destructive, so safety is partly covered. The description adds that the copy can target a different sprite, but does not disclose whether an existing destination cel is overwritten (potential content loss), nor the live-vs-batch backend implications. Some added context, but a key mutation consequence is left 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?

A single well-formed sentence with the operation front-loaded and the optional extension parenthetically scoped. No wasted words, though it is quite terse for a 10-parameter mutation tool.

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 10-parameter mutation with no output schema and minimal annotations, the description omits the meaning of the x/y parameters and the overwrite/return behavior. Annotations carry the safety profile, which lowers the bar, but the description leaves gaps an agent would need to close by opening the schema.

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?

With 10 parameters and only 60% schema description coverage, the description's mention of 'another layer/frame' and 'another open sprite' loosely maps to toLayer/toFrame/sprite, but adds no syntax or format detail. The x, y coordinates go entirely unaddressed in both the description and (by coverage gap) parts of the schema, so it only marginally compensates.

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 (Copies) and resource (a cel's image) with the destination scope (another layer/frame, optionally another sprite). It distinguishes the operation from sibling tools like link_cels (which links rather than copies) and duplicate_layer (which duplicates whole layers). It stops short of explicitly naming a sibling, but the function is unambiguous.

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?

The description implies when it applies (moving a cel's image to a target) but offers no explicit when-to-use vs alternatives, no prerequisites, and no note about how it differs from link_cels or get_cels/update_cel workflows. Nothing routes the agent among the copy-adjacent siblings.

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