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

Annotations already flag destructiveHint=true, but the description adds the details that actually matter: irreversibility, the 30-day name reservation, exactly what data is destroyed, and a connection-scope availability limit. These are traits the agent cannot infer from the annotations alone.

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 tight sentences, front-loaded with consequences and followed by the guardrails. No filler and no repetition of the tool name or title.

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?

A destructive, no-output-schema tool with two fully documented parameters. The description covers consequences, irreversibility, prerequisites and confirmation, which is everything needed to call it safely; return values are irrelevant for a deletion.

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 both parameters already document themselves, including that confirm must be the exact site name. The description restates the confirm ritual ('pass its name again as confirm') without adding syntax or edge-case behavior beyond the schema, so the 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?

Names a specific verb and resource and immediately enumerates the blast radius: files, version history, form messages, custom domains, visitor stats. The phrase 'a whole site' distinguishes it from siblings like delete_file and delete_post without needing to name them.

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 gate — 'Only do this when the owner has asked for this site to be deleted' — plus a precondition ('Only available when the connection covers all sites') and a confirmation ritual. It stops short of naming narrower alternatives such as delete_file for partial cleanup, so it is clear context rather than full routing guidance.

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