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

Annotations already mark this as read-only-false, destructive, and idempotent; the description adds valuable context beyond that: it must be the authenticated administrator's exact choice, inferred selections are forbidden, and a changed snapshot invalidates the supplied revision. It does not detail the destructive impact of applying, but given annotation coverage the additional context is solid.

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-load the core action and then deliver the most important constraints: no inference, fresh selection on snapshot change, and no email or upload. Every sentence earns its place with no filler.

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 destructive, idempotent mutation with four required parameters and no output schema, the description covers the key prerequisites and exclusions. It would be more complete if it told the agent where selectionId and selectionRevision come from, but the review-then-apply workflow is reasonably inferable from the constraints given.

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 only 50%, with selectionId and selectionRevision undocumented in the schema; the description partially compensates by tying them to 'the exact library selection and revision' and warning that a changed snapshot requires a fresh selection. It still does not explain how to obtain these IDs or confirm the relationship between them and the current snapshot, so the added value is moderate.

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 'Apply the exact library selection and revision', a specific verb and resource, and clarifies it must be the admin-reviewed choice rather than an inferred one. This distinguishes the tool from siblings like helvabase_apply_library_promotion and the prepare/inspect/confirm dossier-library-access steps.

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 gives clear behavioral conditions: never apply an inferred selection, and obtain a fresh selection when the snapshot changes. It also removes false prerequisites by stating no email code is needed and no upload is performed, though it does not name the exact sibling tools to use instead.

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