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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and the description is consistent, reinforcing that it 'opens nothing by itself.' It adds genuinely useful context beyond annotations: the return shape (screens, buttons, fields) and the fact that no official API or Zapier app exists, which explains why browser automation is required.

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?

Front-loads the core action and the 'opens nothing by itself' caveat, then the handoff to browser tools. The trailing API/Zapier note is somewhat verbose but earns its place by justifying 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 output schema, the description carries the burden of explaining return values, and it does so ('step by step (screens, buttons, fields)'). Combined with the browser-tool handoff, an agent has enough to call it and act on the result; only the exact output format remains unspecified.

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 baseline is 4. The description correctly implies no inputs are needed and focuses on the return content instead.

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?

States a specific verb and resource ('Book appointment in the user's own Planfy account') and immediately clarifies the actual behavior: it returns step-by-step instructions rather than performing the booking. It does not explicitly contrast with planfy_reschedule_appointment, but the verb/resource pairing is unambiguous enough to distinguish it from the list/find siblings.

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?

Gives a clear usage path: call this to get the steps, then execute them with the cotlet_browser_* tools in the Planfy Cloud Browser. It does not state when to prefer this over planfy_reschedule_appointment, but the booking-vs-reschedule distinction is implied by the name and purpose.

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