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

Beyond destructiveHint=true, it discloses that deletion is permanent by default because media has no useful trash, that it succeeds even while referenced by a block attribute, featured image, or site icon, and that usedBy enumerates those references. This is exactly the behavioral context an agent needs before a destructive call.

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 sentences and a rules line, with the permanence caveat front-loaded ahead of the in-use warning. Dense and largely waste-free, though the trailing 'Rules:' fragment reads slightly clipped.

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?

An output schema exists (covering usedBy return data), annotations carry the destructive hint, and the schema fully documents both parameters. The description adds the domain contract reference and the user-notification duty, leaving nothing an agent needs in order to call this safely.

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%: force's default-true/trash semantics and mediaId's 'see list-media' pointer are already documented in the schema. The description's 'permanent by default' phrasing echoes the schema rather than adding new syntax or format detail, so the baseline 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 states a precise verb+resource ("Delete a media item") and reinforces scope with the permanence-by-default parenthetical and the note that it fires even when the item is in use. An agent can distinguish it from the many other delete-* siblings (delete-icon, delete-block, delete-content) without opening a 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?

It supplies a clear precondition (read the site-assets-contract skill doc before the first call) and a downstream action (tell the user which places lose the image). It does not, however, compare when to reach for this tool versus adjacent alternatives such as uploading a replacement or trashing instead of forcing, so exclusions are absent.

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