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

Annotations indicate readOnlyHint=false, destructiveHint=false, openWorldHint=true, which are consistent. The description adds key behavioral details: the code is user-provided via email, and success returns a delegation_token. It does not contradict annotations and supplements them with practical constraints.

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 description is three sentences long with no filler. It front-loads the action (submit code), explains the context, and ends with the critical limitation (agent cannot obtain code). Every sentence adds unique value.

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?

Given the tool has 3 parameters, no nested objects, and an output schema exists, the description fully covers the workflow: it specifies the input requirements, the user's role, and the output outcome. No gaps or missing information for an agent to use the tool 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 baseline 3 is appropriate. The description adds meaning by explaining that 'code' is a 6-digit code from the buyer's email and 'device_code' comes from request_delegation, while 'site_id' is optional. This clarifies the source and type of each parameter beyond the schema.

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 clearly states the tool submits a 6-digit code to approve delegation and returns a delegation_token for checkout/payment. It distinguishes from sibling tools like request_delegation and submit_payment_otp by specifying the exact input and outcome.

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?

The description explicitly informs that the agent cannot obtain the code itself — the user must read it from their email and provide it. It also ties the tool to request_delegation. While it doesn't state when not to use it, the context is clear enough for an agent.

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