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

The annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is covered structurally. The description still earns credit by adding what actually gets destroyed — the contact's audience memberships — and reinforcing irreversibility with "Permanently," context the annotations cannot express. It doesn't cover auth requirements or behavior when the contact is missing, which keeps it from 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?

One sentence with no filler, and the most consequential fact (permanence plus cascade) is front-loaded. Nothing here is redundant with the title or annotations.

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 one-parameter mutation with full schema coverage and rich annotations, the description supplies the missing piece — scope of deletion. Minor gaps remain around what happens on a nonexistent ID and whether the contact is also removed from automations, but no output schema is needed to be explained.

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 single `id` parameter already documents the con_xxx-or-email format, so the schema does the heavy lifting. The description adds no additional meaning about identifier handling, making the baseline 3 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 names a specific verb and resource ("Permanently delete a contact") and adds the side effect on audience memberships, which goes beyond a bare restatement of the name. It doesn't distinguish itself from the sibling bulk-delete-contacts or remove-audience-subscriber, so an agent must infer the single-vs-many boundary.

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?

No explicit when-to-use or when-not-to-use guidance is given. The description never points to bulk-delete-contacts for multi-record deletion or to remove-audience-subscriber when only membership removal is wanted, leaving the choice to inference from the name alone.

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