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

With annotations denying readOnly but asserting idempotent and non-destructive, the description adds meaningful context: it explains the two outcomes (sign-up link vs Stripe page) and crucially directs the agent never to collect bank or tax details in chat. This adds security/privacy behavior not present in annotations.

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-loaded with the controlling condition ('For an APPROVED agency') and then the behavior and the safety constraint. It is a dense single sentence but every clause earns its place; no filler.

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?

No output schema exists, so the description carries the burden, and it does explain what the agent gets back (setup status plus a link, with the link type depending on completion). Complete enough to invoke correctly, though it does not detail error or non-approved-agency cases.

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 takes no parameters and has 100% schema coverage, so there is nothing for the description to disambiguate. Baseline of 4 applies for a zero-parameter tool.

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+resource ('Set up or open agency payouts') and clearly defines scope: determines whether an APPROVED agency's commission payouts are set up with Stripe and returns a link to open. This distinguishes it from sibling account tools like my_agency, my_agency_access, and update_my_agency_details.

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?

Provides a clear precondition ('For an APPROVED agency') that tells the agent when the tool applies. It does not name alternative tools or explicitly state exclusions, so it falls short of full when/when-not routing, 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.