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

Annotations already declare destructiveHint=true and idempotentHint=true, but the description adds real context beyond them: it names exactly what is destroyed (upload and finished files), states the deletion is immediate rather than deferred by the 24-hour window, and warns 'This cannot be undone.' It does not cover behavior for an in-flight scan or what happens to a subsequent reference to the scan_id.

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, each carrying distinct information: what is deleted and when, the authorization condition, and irreversibility. The destructive warning is front-loaded and nothing is redundant.

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 full annotation coverage and no output schema, the description covers scope, timing, authorization, and irreversibility. Only edge cases, such as deleting a scan that is still processing or whether the scan disappears from list_my_scans, are unaddressed.

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% and the single scan_id parameter is documented with its regex pattern and provenance ('the scan_id fix_scan or list_my_scans gave'). The description adds no parameter-level meaning, so the 3 baseline 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?

The description gives a specific verb and resource ('Delete a book's upload and finished files') plus the distinguishing timing detail that the removal happens immediately instead of after the 24-hour retention window. It does not explicitly contrast with cancel_scan, the nearest sibling, so an agent must infer that cancel stops a job while this destroys stored files.

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?

It gives an explicit gating condition: 'Use it only when the user asks to delete the book,' which is a clear when-to-use rule and implicitly excludes proactive deletion. It stops short of naming alternatives such as cancel_scan for an in-progress job or simply waiting out the 24 hours, which would complete the routing picture.

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