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

Annotations already flag destructiveHint=true and readOnlyHint=false, so the description earns credit for adding context beyond them: the delete also removes "its file", the action "cannot be undone", the call is free, and the response is a simple {ok}. It does not cover permission requirements or whether shared/staged copies are affected.

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 plus a compact Args/Returns block, with irreversibility front-loaded. The "Free." cost note leading the description is slightly unusual placement but still earns its place as decision-relevant information.

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 destructive tool with annotations and no output schema, the description covers cost, irreversibility, the side effect on the stored file, and the return shape. The only gap is auth/scope behavior for shared or staged library items.

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 100% and the single parameter is fully documented in the schema itself. The description's "library_id: from library_list" restates that provenance rather than adding new meaning, so the baseline of 3 is appropriate.

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 uses a specific verb and resource ("Delete one item and its file from the WEB Library") and defines the scope precisely as a single item. It does not explicitly name or contrast with the delete-like siblings (persona_delete, studio_delete_project), but the library scope makes the target unambiguous.

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?

Usage is implied by the name and the irreversible nature of the call, and the pointer "library_id: from library_list" hints at the lookup-then-delete workflow. There is no explicit when-to-use/when-not guidance and no mention of how this differs from the other delete tools in the sibling set.

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