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

With all hints false, the description carries the transparency burden and does add meaningful protocol context: fresh nonce proof, AES-256-GCM local sealing with key_kind=controller_key, legacy bearer fallback, and per-bag ownership. It does not discuss side effects, persistence, or failure behavior, but it discloses the most important auth/data-isolation constraints.

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 sentences, no filler, with the endpoint and required payload front-loaded. It is compact and efficiently ordered, though the dense jargon ('GRITH-CONTINUITY/1', 'key_kind=controller_key') makes it less readable than a plainer equivalent.

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 seven-parameter write operation with a nested envelope and no idempotency/read-only hints, this is under-specified: it omits the actual effect of the write, any success/failure semantics, and why an agent would choose this tool. The output schema covers the return shape, but the description itself leaves too much domain context implicit.

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?

The schema already documents 5 of 7 parameters, and the prose reinforces the relationship between the bag, envelope, and controller-key proof without fully explaining bag/body. The envelope encryption detail adds some meaning beyond the schema's 'holder-sealed envelope' but the description does not compensate for the two undocumented parameters.

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 the exact HTTP verb and resource ('POST /api/locker') and the name locker_write reinforces the write intent, so the basic purpose is clear. It does not explicitly distinguish itself from sibling locker tools such as locker_seal or locker_purge, 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?

It supplies useful preconditions: a fresh controller proof, a locally sealed envelope, and the note that Bearer {bag, body} is legacy. However, it never states when to choose locker_write over the nearby locker_desk/locker_seal/locker_purge, leaving the decision largely implied by the tool name and endpoint.

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