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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, so the safety profile is known; the description reinforces it with 'opens nothing by itself'. It adds real context beyond annotations by describing the return shape (screens, buttons, fields) and the required follow-up path via the Cloud Browser. The note about Club OS's API-only-by-email constraint explains why the browser route is needed.

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 core purpose and the 'opens nothing by itself' caveat are front-loaded, which is good. However, the final sentence about Club OS's official API and support-email onboarding is peripheral detail that does not help an agent invoke this specific tool, and the description is dense as a single block.

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?

With no parameters and no output schema, the description carries the burden of explaining the return value, and it does so explicitly ('returns how to do it in Club OS step by step (screens, buttons, fields)'). Combined with the read-only annotation and the stated follow-up browser tools, an agent has what it needs to call this correctly; only sibling routing 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?

The tool takes zero parameters and the schema coverage is 100%, so there is nothing for the description to disambiguate. Baseline for a no-parameter tool applies, and the description correctly implies no inputs are needed.

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 states a specific resource and action ('write off an invoice') and then clarifies the actual behavior: it returns step-by-step instructions rather than performing the write-off. This is a clear verb+resource statement that an agent can act on. It does not, however, distinguish itself from plausible siblings such as club_os_request_a_bulk_pt_invoice_write_off or club_os_comp_an_invoice.

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?

Usage is implied rather than stated: call this to get the procedure, then execute it with cotlet_browser_* tools in the Cloud Browser. That sequencing is useful guidance. But there is no explicit when-not or alternative routing to the bulk write-off, comp, waive, or refund tools that overlap with this one.

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