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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is largely covered. The description adds nothing beyond that: it does not say whether deleting a folder-style key removes nested keys, whether a missing key errors or is a silent no-op (relevant for the idempotent claim), or that the deletion is irreversible.

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?

A single short sentence with zero filler and the action front-loaded. It is efficient, though the extreme brevity for a destructive tool borders on under-specification rather than tight editing.

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, mutation-capable tool with no output schema, the description omits important operational detail: behavior when the key does not exist, the '/' folder-prefix deletion semantics implied by the key format, and any required auth context beyond the optional passport_token. Annotations carry the safety hints, but the description leaves genuine gaps an agent would care about before deleting.

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%, so key format (1-200 chars, allowed character set, '/' as folder separator) and instance_id sourcing from buy/list_utilities are already documented. The description adds no additional parameter meaning, so the baseline of 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 (delete) and resource (a key in your memory locker), which clearly separates it from the read-oriented siblings locker_get and locker_list and the write-oriented locker_put. It does not name or contrast those siblings explicitly, so it falls short of a 5.

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?

There is no when-to-use guidance, no prerequisites (e.g., that a locker must already contain the key), and no reference to the alternatives such as locker_put for overwriting or locker_get for inspecting first. The agent must infer all routing from the tool name alone.

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