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

Annotations already cover readOnlyHint=false, destructiveHint=false, idempotentHint=false, and openWorldHint=false, so the safety profile is known. The description adds meaningful extra context: required OAuth scope ('order:prepare'), the fact that it changes buyer or order state, the short-lived nature of the confirmation link, and the explicit exclusion of submission/payment.

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 tight sentences, front-loaded with the trigger condition and core action, then the approval requirement, then the scope and state-change note. No wasted words.

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 state-changing order preparation step, the description covers the prerequisite, the effect, the required OAuth scope, the non-submission boundary, and the human approval flow. Output schema exists, so return values need not be explained.

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 tool has zero input parameters, so there are no parameter semantics to document. Per calibration, a zero-parameter tool starts at baseline 4; the description cannot add param-level meaning beyond that.

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?

Specific verb ('prepare') and resource ('exact order summary and a short-lived browser confirmation link'), with clear scope that it does not submit or pay. Distinguishes itself from siblings like submit_order and get_checkout by naming the prerequisite and the follow-up action.

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?

Explicitly states when to call it ('After get_checkout validation succeeds'), what must happen next ('buyer must personally approve that summary before submit_order'), and what it does not do (does not submit or pay). Names the alternative/subsequent tool, leaving no ambiguity.

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