skin_validate

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds real behavioral context beyond that: the validation scope is limited to technical compatibility (not art quality or in-game acceptance) and the path is constrained to the output root. It omits what a failure result contains, which keeps it below 5.

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?

Three short sentences, front-loaded with the action, then the key invocation constraint, then the boundary of the check. No filler and nothing repeated from the schema or annotations.

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 two-parameter read-only validator with no output schema, the description covers purpose, scope limits, and the model requirement well. The remaining omission is the shape of the result (pass/fail fields, error reporting), which matters somewhat because no output schema exists to document it.

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 carry the load, and it does: it explains why `model` (classic/slim) must be provided explicitly and scopes `path` to the output root. It does not state the consequence of an incorrect model value or what an invalid path does, leaving a small gap.

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 and object ("Validate a PNG inside the output root") and scopes the check to technical compatibility rather than artistic quality or in-game acceptance. Siblings (skin_schema, skin_build, skin_preview) are not named or differentiated, but the purpose is unambiguous on its own.

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?

Gives clear usage context: the model argument must be supplied correctly because the PNG alone cannot disambiguate classic/slim geometry, and explicitly bounds what the tool does not judge. It stops short of saying when to call it relative to skin_build or skin_preview, so it is clear context without explicit alternatives.

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