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

Annotations declare non-read-only, open-world, non-idempotent, non-destructive, but the description adds the concrete side effect (an email is sent to the user), the plan transition, and the resulting 50,000 requests/month quota — none of which the annotations convey. It stops short of stating whether codes expire or what happens if the email is wrong/unreachable.

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: effect first, prerequisite second, hand-off third. No filler, and the ordering matches how an agent should actually act.

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 one required parameter, full schema coverage, no output schema, and a clear two-step flow, an agent has enough to call it correctly. Minor gaps remain around return value and code validity window, but nothing blocking.

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 single email parameter is already documented; the description still adds a real behavioral constraint beyond the schema ('Ask the user for their email first; never guess it'), which meaningfully changes how the agent sources the value.

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 and resource ('Emails the user a 6-digit code') plus the outcome ('moves this connection from the trial to the free plan'). It explicitly hands off the follow-up step to the sibling aura_verify_email, so an agent can distinguish the two without opening either 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?

Gives an explicit prerequisite ('Ask the user for their email first; never guess it') and an explicit next action ('Then ask them for the code and call aura_verify_email'). The alternative and the condition that selects it are named directly.

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