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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description is consistent with them, explicitly saying it "opens nothing by itself" and only returns procedural guidance. That is useful corroboration beyond the annotations, though it adds little about the shape or limits of the returned instructions (length, whether it varies by account).

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 point (returns instructions, executes nothing, follow up with browser tools) is front-loaded and earns its place. The closing note about ResDiary's official API is tangential and the "checked 31 Oct 2026" stamp reads as boilerplate rather than actionable detail.

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 zero-parameter, no-output-schema helper tool, the description covers what it returns, that it is non-destructive, and how to complete the actual task. Only the granularity of the returned instructions and any account-specific caveats remain unstated, which is minor.

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 the schema already carries the full contract; the description correctly implies no inputs are needed. There is no parameter surface for the description to explain further.

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 guest notes in the user's own ResDiary account") and immediately clarifies that the tool only returns step-by-step instructions rather than performing the action, which resolves the ambiguity of the name. It does not explicitly contrast itself with the sibling resdiary_create_a_booking or resdiary_cancel_a_booking tools, but the resource is distinct enough for an agent to tell them apart.

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 operating context: use this to learn the steps, then execute with the cotlet_browser_* tools in the user's ResDiary Cloud Browser. It also explains why the browser route is needed (official APIs limited to approved integrations). It stops short of stating explicit exclusions or prerequisites for alternative tools.

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