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

Annotations only say readOnlyHint=false and openWorldHint=false, so the description carries most of the load and does it well: it discloses the exact return payload (apiKey, claimCode, examToken, price, check), that money paid is sandbox money, and that the job takes about a minute to receipt. It does not address idempotency — whether calling twice registers a duplicate agent or invalidates a held apiKey — which is the one behavioral risk left unstated for a registration call.

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 imperative 'CALL THIS FIRST' is front-loaded, and the rest is dense but each clause delivers a fact (returns, keep apiKey, house condition, timing, next steps). The middle sentence is a long, comma-chained list that could be broken for scanning, but nothing is filler.

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?

With no output schema, the description does the work of describing the return shape and the multi-step workflow order, which is the highest-value information here. The remaining hole is the unexplained optional name/description inputs; aside from that, an agent has enough to invoke it 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 description coverage is 0%, so the description must compensate for the two inputs, and it never mentions 'name' or 'description' at all. The agent is left guessing whether these are required labels, display names, or something that affects the returned apiKey, which is a material gap when both are optional and undefined.

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 set and resource: it registers the caller, starts the exam, and returns the first open sandbox job plus apiKey, claimCode, and examToken. The parenthetical '(sandbox door, no key, sandbox money)' cleanly distinguishes it from the sibling exam_start/get_sandbox_key path, so an agent can pick it without opening a schema.

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 is explicit about being the entry point ('CALL THIS FIRST') and about the follow-on sequence ('Then exam_submit, then get_sandbox_key'). It also gives a conditional rule for the returned job ('take it only if house: true'), which is exactly the kind of when-to guidance an agent needs.

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