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

Annotations establish a non-read-only, non-destructive, non-idempotent mutation, and the description adds meaningful context beyond them: the copy is created inactive with a copy label, the original is preserved, and the operation consumes a plan variant slot. It stops short of saying whether repeated calls create additional copies (non-idempotent) or what error occurs at the plan limit.

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 and result, then the side effects, then the return. No filler and nothing repeated from structured fields.

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 one-parameter mutation this covers action, side effects, plan impact, and return shape (the copy and editor link). A pointer to set_active_variant for activating the resulting inactive copy would close the remaining 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?

Only one parameter (variantId) and the schema provides zero description coverage. The description implies the ID refers to the source variant being copied, but never states that explicitly or clarifies whether the ID must belong to the current project. Baseline 3 given the single obvious parameter.

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 variant's saved content and translations) with the resulting artifact (a new inactive variant with a copy label). It is clearly distinguishable from create_variant in intent, though it never names the sibling to make the contrast explicit.

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 described behavior implies the use case (clone an existing variant rather than build one from scratch), but there is no explicit 'use this when…' guidance and no mention of alternatives such as create_variant for a from-scratch variant. The plan-limit warning hints at a pre-condition but does not frame it as guidance.

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