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

With no annotations, the description carries the entire burden and does so well: it discloses that the key is shown once and must be kept, the exact auth header format, concrete rate limits (30/min, 3 holds, 5/day), how email verification raises them, a 3-keys-per-day-per-address cap, and that notify_secret is returned once. This is exactly the operational context annotations would otherwise provide.

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?

The key-issuance fact and the auth format are front-loaded, and the dense sentences on limits and verification each carry real information. It reads slightly run-on and crammed, but nearly every clause earns its place.

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?

There is no output schema, so the description must explain return values — and it does: the key appears once in the answer, plus notify_secret for push. Combined with limits, the limit-increase path, and the key-management page, an agent has everything needed to call this correctly.

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%, so all four parameters including notify_url are already documented, making 3 the baseline. The description adds light context for owner_label ('the plain name business owners will see next to a job') and agent_name ('what your agent is called'), but omits notify_url entirely and mostly echoes schema text.

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 outcome — 'Get your own key, no human needed' — for a self-serve registration tool, which is clearly distinguishable from transactional siblings like book, hold, and cancel. It stops short of a clean 'registers an agent and issues a key' verb+resource framing, but intent is unmistakable.

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 communicates the self-serve context ('no human needed') and gives an explicit exclusion: 'The demo key needs no registration,' steering agents away when a demo key suffices. It does not explicitly state this must be called before the other tools, so it falls just short of full when/when-not guidance.

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