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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds crucial context the annotations cannot: the tool performs no action at all, only returns a how-to guide, and must be followed by cotlet_browser_* calls. It also discloses that Invoice2go has no public API or self-serve keys, explaining why the browser path is the only option. This resolves the tension between the tool's 'send' name and its read-only annotation.

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?

It is front-loaded with the critical caveat ('returns how to do it... opens nothing by itself') before the next-step instruction. The closing sentence about the official API is long and contains an oddly future-dated verification note ('checked 8 Nov 2026'), which is somewhat tangential, though it does justify the browser-based approach.

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, no output schema, and rich annotations, the description covers everything an agent needs: what the return value looks like (screens, buttons, fields), that nothing is executed, and which tools to call next. Nothing material is missing for correct invocation.

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 is an empty object with additionalProperties=false, so there is nothing for the description to disambiguate. Baseline 4 applies; the description correctly implies no input is required and that account context comes from the user's connected Cloud Browser session.

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 verb and resource (send a payment reminder in Invoice2go) and then immediately corrects the likely misreading by explaining the tool returns step-by-step instructions rather than performing the action. The one weak spot is the opening sentence, which reads like an execution claim until the second sentence clarifies it. An agent can still tell this apart from invoice2go_send_invoice and cotlet_browser_* without opening a schema.

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?

It explicitly routes the agent to the alternative: 'then do it with the cotlet_browser_* tools in the user's Invoice2go Cloud Browser', and clarifies the tool itself opens nothing. It gives clear context for the two-step workflow but does not state prerequisites or when-not-to-use this tool (e.g. if the account is already connected or the browser session is missing).

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