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

Annotations already declare readOnly, idempotent, non-destructive and closed-world; the description adds the non-obvious behavior that this returns narrative step-by-step instructions (screens, buttons, fields) rather than performing anything, which annotations cannot express. It does not say what happens if the user is not logged into Minuba or how the guidance is scoped to their account state.

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 behavior and the follow-up hand-off to cotlet_browser_* are front-loaded in the first two clauses. The trailing paragraph on Minuba's REST API is supporting context that justifies why a browser route is needed, but it is longer than necessary for the decision at hand.

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 params and no output schema, the description carries the burden of explaining the return value, and it does: step-by-step screens, buttons and fields. It also explains the handoff to browser tools. What remains unaddressed is preconditions (an active Minuba browser session or login) needed before the guidance is actionable.

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, so there is no schema semantics for the description to extend; baseline applies. The description could have noted that account/user context is inferred implicitly, but that is a minor omission.

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 (sending an invoice in the user's own Minuba account) and immediately clarifies that the tool does not perform the action: it 'Returns how to do it in Minuba step by step' and 'opens nothing by itself.' This corrects the misleading verb in the name/title, though the agent must read past the name to learn the tool is guidance-only.

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 names the follow-up path explicitly ('then do it with the cotlet_browser_* tools in the user's Minuba Cloud Browser'), which is exactly the alternative an agent needs after getting steps. It also rules out the official REST API as an option by noting no self-serve key and no MCP server, though it never states when not to use this tool (e.g., if a browser session isn't available).

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