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

Annotations already declare destructiveHint, idempotentHint, openWorldHint and non-readOnly, so the safety profile is carried. The description adds genuinely new context: the operation is refused for attached firewalls, and it requires the `network.write` scope. It doesn't say whether the deletion is recoverable, though the precondition disclosure is the more valuable half.

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, front-loaded with the operation, then the blocking condition, then the permission scope. No sentence restates the title or wastes tokens.

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 delete with full annotation coverage and no output schema, the description supplies everything an agent needs to call it correctly and anticipate the failure mode: precondition, refusal behavior, and required scope.

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?

Only one parameter and the schema already documents it at 100% coverage, including the cross-reference to `list_firewalls`/`create_firewall`. The description adds no format or lookup detail beyond what the schema supplies, so 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 specific verb (deletes) and resource (firewall) and immediately qualifies scope with a precondition: the firewall must be attached to no machine. That qualifier also cleanly separates it from sibling `detach_firewall`, which the agent might otherwise confuse it with.

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 gives an explicit when-not ('Refused while it protects one') and the corrective action ('detach it first'), which effectively routes the agent to the detach path. It stops short of naming the sibling tool `detach_firewall` by name, so the routing is inferred rather than explicit.

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