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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds value beyond that by disclosing the cascade effect — the file also disappears from any queues that reference it — which is a non-obvious side effect not present in the annotations. It omits auth/permission requirements and error behavior, so it falls short of a 5.

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 zero filler: the action, the irreversibility plus cascade consequence, and the API mapping. The most important constraint (permanent, irreversible) is front-loaded immediately after the verb.

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 single-parameter destructive tool with annotations covering the safety profile and no output schema, the definition supplies what an agent needs: the effect, the irreversibility, and the downstream consequence. Only permission requirements and failure modes are absent, which keeps it just short of complete.

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 sole parameter's meaning ('Media (storage) UUID.') is fully documented there. The description adds only the informal phrase 'media file', which does not extend the schema's semantics; 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 delete a media file from the library') and pins the scope to media, which cleanly separates it from the many sibling delete_* tools that act on folders, streams, and tags. An agent can select it without opening the 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?

Usage is implied by the description and the resource name, and the irreversibility warning nudges the agent to confirm intent. However, it never names alternatives (e.g., update_media, move_files_to_folder) or states prerequisites, so the when-to-use routing is left to inference.

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