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

Annotations already declare destructiveHint=true, idempotentHint=true, and readOnlyHint=false, so the safety profile is covered. The description adds genuinely non-redundant context: the delete is a soft delete ('moves to the bin') recoverable via restore_deleted, and it stays scoped to the same product. It doesn't discuss cascading effects (line items, documents referencing the variant), which keeps it from a 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?

Two tight sentences, action and recovery semantics front-loaded, alternatives trailing. No wasted clauses.

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, no-output-schema mutation, the agent knows what happens to the entity, that it's recoverable, and what tools to use instead. Missing only the side effects on related records, which is minor here.

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 coverage is 100% with both parameters described, so baseline is 3. The description mentions 'by id' and implies the parent product context, but doesn't resolve the schema's odd signal where id is described as 'Required in practice' yet absent from the required array — that ambiguity is left to the schema alone.

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 resource ('Delete a product variant by id') and immediately distinguishes itself from two siblings by naming restore_deleted and save_variant. An agent can route correctly without inspecting the schema.

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?

Explicitly covers the alternatives: restore_deleted for recovery and save_variant for create/edit. Both the when-to-use-this and the when-to-use-something-else cases are stated.

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