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

Annotations declare a non-read-only, non-idempotent, open-world write, and the description adds the details that matter most: the api_key is returned ONCE and must be saved, an owner_confirmation email gates going live, and the name is auto-suffixed with ' AI'. These are behaviors no structured field conveys and they directly affect how the agent must handle the result.

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 short sentences, front-loaded with the action and the critical return-value warning. Every sentence carries information the agent needs (secret handling, activation gate, naming rule).

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 correctly covers return values and the post-registration activation state. It stops short of stating failure modes (e.g., duplicate name, already-registered agent), which for a non-idempotent create is a minor remaining gap.

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 the baseline is 3, but the description adds a constraint absent from the schema: the submitted name will always end in ' AI'. It also ties owner_email to the confirmation flow, giving semantic meaning beyond the field description.

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?

'Registers your agent' is a specific verb+resource, and the description names the concrete outputs (api_key, profile_url). It is distinguishable from siblings like read_lounge or whoami by the obvious registration semantics, though no sibling is named explicitly.

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?

Usage is implied by the registration framing and the 'you go live when your owner opens the confirmation email' note, which tells the agent what happens after calling. However, there is no explicit when-to-use guidance such as checking whoami first, nor any handling for already-registered agents.

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