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

Annotations already flag destructiveHint=true and idempotentHint=true, so the safety profile is known. The description adds genuinely useful context beyond that: the 50-item ceiling and, importantly, that failures are reported per item (e.g., publishing_in_progress), implying partial-success semantics rather than all-or-nothing. It stops short of saying whether successfully deleted items roll back on partial failure.

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 with the destructive operation and scope front-loaded, followed by failure behavior and the usage condition. No filler and every sentence carries distinct 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?

With no output schema, the description helpfully sketches the failure surface (per-item errors) and the item cap. It lacks permission/authorization requirements and any note on whether items must be unpublished first, which would matter for a destructive bulk tool.

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?

There is only one parameter and schema description coverage is 100%, with the schema itself documenting the max-50 limit. The description's 'by id' and 'up to 50' restate schema facts rather than adding format or ordering semantics, so the baseline 3 applies.

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 ('permanently deletes ... library items by id'), with a clear batch scope ('up to 50 ... in one call') and eligibility constraint ('queued, draft or archived'). The bulk-vs-single distinction from delete_library_item is implied by the 50-item cap rather than stated explicitly.

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?

'Applies when the user explicitly wants items removed for good' gives a positive invocation condition and implicitly warns against casual/soft deletion. However, it never names alternatives such as bulk_archive_library for reversible removal or delete_library_item for single items, and doesn't state when this tool should not be used (e.g., published items).

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