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

Beyond the annotations it discloses the legal consequence (joining accepts the partner terms on behalf of the entity), the payout mechanics (Stripe cash or Arrakis GPU credit, requiring payouts setup in console), and that re-joining returns the same code. It also documents the '?tag=' link convention, which no structured field covers.

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?

Front-loads the benefit and the returned artifacts, then layers consent, terms, cost, and scope. It is dense but nearly every clause carries decision-relevant information; the Stripe/credit payout detail is the one passage that could be trimmed for an agent audience.

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 one-parameter mutation with no output schema, the description covers the return values (code, link, message), the consent/terms prerequisite, the auth scope, and idempotency. Nothing an agent needs in order to call it safely is missing.

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?

With one parameter at 100% schema coverage the baseline is 3, but the description reinforces the provenance of terms_version ('the terms_version you read', tied to get_partner_earnings) so the agent understands it must be fetched, not invented. It adds little else about the field's format, hence not a 5.

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 ('Join the Arrakis partner program') plus the concrete artifacts produced ('your own partner code, link and a message to share'). This clearly separates it from the read-only sibling get_partner_earnings, which only reports earnings/terms.

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 gating condition ('Only join if the person or company you act for agrees'), a prerequisite chain ('Pass the terms_version you read', sourced from get_partner_earnings), and an auth requirement ('Needs a token with the billing scope'). It also notes the free/idempotent path so the agent knows re-joining is safe.

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