Transfer an animation to another skeleton

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

Beyond the annotations (readOnly=false, destructive=false), the description discloses that it reports what matched, was renamed, or could not move, that the write is dry-run by default, and that copies mode surfaces conflicts resolved via 'prefer' before writing into the base. That is meaningful operational context an agent would otherwise have to guess.

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 first sentence is front-loaded and efficient, but the second sentence is compressed to the point of being hard to parse ('copies: merge mode for animators on copies of one project') and mixes mode description with output behavior in a single semicolon chain.

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 16-parameter mutation tool with no output schema and a nested map/retarget structure, the description covers the core copy-and-merge semantics and the dry-run safety default but leaves a substantial share of parameters and the editor/staging behaviors undocumented, which is a meaningful gap.

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 only 31% across 16 parameters, so the burden falls on the description. It does explain the matching order (exact, then map, then case/separator-insensitive), the map and prefer objects, the copies array, and that 'to' is the base target — but editor, replace, retarget, normalize, allowUpgrade, stagingPath, fromSkeleton/toSkeleton, and the from/name/animation trio remain unexplained.

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 opens with a specific verb+resource ('Copies an animation to another skeleton or project') and names a second mode ('copies: merge mode'). That distinguishes it reasonably well from siblings like spine_derive_animation or spine_generate_animation, but the two modes are not clearly named as modes, so an agent must parse the second sentence to see the split.

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?

It says the tool is 'dry-run by default' and that the add step behaves 'like spine_add_animation', which gives some selection context, and the copies clause implies a multi-animator workflow. However, it never states when to choose this over spine_add_animation or spine_import_layers, and no explicit exclusion is given.

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