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

Annotations already flag destructiveHint=true, so the lower bar applies, yet the description still adds real context: permanence, the refusal condition while a render or plan is in flight, and that Library assets are not cascaded. It does not state whether an undo or confirmation step exists.

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?

Front-loaded with cost and destructiveness in the first clause. The Args/Returns blocks are near-duplicates of the schema and the {ok} return, but they cost little and keep it readable.

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 no output schema, the description covers cost, irreversibility, blocking conditions, and collateral effects on Library content. Only the failure/response shape beyond {ok} is thin.

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 schema entry already says the id comes from studio_list_projects; the description's "project_id: project" restates the field without adding format or sourcing detail.

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 project") and immediately scopes it against the sibling concern by noting that rendered videos in the Library are unaffected, which is what separates it from library_delete.

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?

Gives an explicit precondition for failure ("refused while it renders or plans") and the cost signal "Free." The note that Library videos survive implies where to go for those, but no sibling is named outright.

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