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

Annotations only say destructiveHint=true, so the description carries real weight by disclosing the default soft-delete semantics ('stops working but stays queryable') and that permanent irreversibly erases the key. It stops short of noting auth requirements, whether a soft-deleted key can be restored, or rate limiting.

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?

Two tight sentences with the key behavior front-loaded; the trailing endpoint reference ('Unkey: POST /v2/keys.deleteKey') is mildly redundant metadata but does not obscure the main point.

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 two-parameter destructive mutation with no output schema, the description covers the critical behavioral facts: what the default does, what permanent does, and that soft-deleted keys remain queryable. Missing return-value and permission details are minor given no output schema exists.

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 100% and the schema already documents both keyId and permanent, including the 'defaults to false' note. The description's explanation of permanent duplicates the schema rather than adding new meaning, 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?

States a specific verb and resource ('Revoke a key') and immediately scopes it with the soft-delete vs permanent distinction, which clearly separates it from siblings like unkey_update_key or unkey_get_key.

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 explains the default behavior (soft delete) and the permanent option, which implies intent, but it never states when to prefer this over alternatives such as disabling via update_key or when a hard delete is warranted. Usage is inferable but not explicit.

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