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

The description adds real behavioral context beyond the annotations: it explicitly says it "opens nothing by itself," which corroborates readOnlyHint=true and destructiveHint=false, and it discloses that Paperless Post has no public API (checked 10 Oct 2026), explaining why a step-by-step guide exists. It doesn't specify the return structure beyond "screens, buttons, fields," but the safety profile is consistent and reinforced.

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 short and front-loaded, stating the action first and the caveats after. The phrase "from ChatGPT, Claude or any AI agent" is mild filler, but it costs little and the API-absence note earns its place.

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 parameterless guide tool with no output schema, the description covers what it does, what it returns (step-by-step screens, buttons, fields), what it does not do, and the next tool family to call. Enough for an agent to invoke it correctly, though the exact return shape is only loosely sketched.

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 4 is the baseline. The description correctly implies no arguments are required for the guide step, and there is nothing further to document.

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 ("Add guests in the user's own Paperless Post account") and immediately clarifies the actual behavior: it returns instructions rather than performing the action. This distinguishes it from action-executing siblings like paperless_post_send_invitation or cotlet_browser_* tools, though it never names a Paperless Post sibling as an alternative.

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 gives clear when-to-use context (you want to add guests) and an explicit follow-up path: use the cotlet_browser_* tools in the user's Paperless Post Cloud Browser after reading the steps. It lacks explicit when-not guidance or a named sibling alternative, which keeps it out of 5 territory.

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