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

Annotations already mark destructiveHint=true, but the description goes well beyond them: it discloses irreversibility, that materials do not go to the recycle bin, that project material cost is lowered, and crucially that the human, not the agent, must supply confirmation fields. This is rich behavioral context that meaningfully affects how an agent should plan and invoke the tool.

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?

The description is short, front-loaded with the key action and consequences, and every sentence earns its place: scope, irreversibility, recycle-bin behavior, and the human-confirmation rule. No wasted words.

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 destructive tool with no output schema and only three simple parameters, the description covers the essential context: what is deleted, the permanent consequence, and the mandatory human-in-the-loop confirmation. It does not mention what happens if the material_id does not exist or whether deletion is idempotent, but these are minor for a tool whose safety-critical aspects are already well covered.

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 67%: confirm and confirmation_phrase already have explicit descriptions in the schema, and the description reinforces the human-only rule. The remaining parameter, material_id, is not described in the schema, and the tool description only indirectly clarifies it via 'delete a material line from a project'. The description adds safety emphasis but no substantial new parameter-level meaning beyond the schema.

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 specific verb ('delete'), a specific resource ('material line'), and a scope ('from a project'). It also emphasizes 'PERMANENTLY' and 'cannot be undone', clearly distinguishing this destructive operation from soft-delete/restore siblings. This leaves no ambiguity about what the tool does.

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?

The description provides explicit invocation guidance: use only with explicit human confirmation, and never auto-fill confirm/confirmation_phrase. It makes clear this is a permanent act on a material line, not a reversible soft delete. However, it does not explicitly name alternatives (e.g., updating the material instead of deleting) or state when not to use it beyond the human-confirmation requirement, so it stops short of a full when/when-not comparison.

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