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

Beyond annotations (readOnly=false, idempotent=false, destructive=false), the description discloses real side effects: the return of the updated view, the bank_onboarding_url Stripe page that must be handed to the person, and the confirmation e-mail sent to PayPal addresses. These are exactly the behaviors an agent needs to complete the flow.

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 first two sentences are front-loaded with purpose and side effects, and the embedded JSON example is compact. The escaped 'Arguments:' echo is slightly noisy but earns its place by showing the body shape.

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 mutation tool with no output schema, the description covers the return value and the payout-specific follow-ups. Minor gap: it does not state whether omitted fields are left untouched or cleared, which matters when all body fields are nullable.

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 top-level schema reports no description on the single 'body' param, so the description's inline example clarifies the body wrapper and the destination/payout pairing. The nested property descriptions in $defs already explain payout modes, country, and paypal_email, so the description mostly reinforces rather than adds new parameter meaning.

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 two concrete resources — where the affiliate link leads (destination) and how commissions are paid (payout). This clearly separates it from kelpo_join_affiliate_program (enroll) and kelpo_affiliate_program (read the program), so an agent can route between them.

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 phrase 'as the person decided' signals this is a write-back of a user's choice, and the destination param is tied to 'one of the destinations listed by kelpo_affiliate_program', giving an explicit prerequisite. No explicit when-not guidance, but the context is clear.

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