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

Resolves the apparent tension between the 'Create' name and readOnlyHint=true by stating plainly that it 'opens nothing by itself' and only returns instructions, screens, buttons and fields. It also explains why — no public Fresha API or developer docs — which is exactly the kind of context annotations cannot convey.

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 purpose and the critical 'opens nothing by itself' caveat in the first two sentences, with the API note as trailing justification. The phrase 'Fresha's official API: Fresha has no public API' is mildly redundant and the dated stamp is fragile, costing a point but not clarity.

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 and no output schema, the description still tells the agent what comes back (step-by-step screens, buttons, fields) and what to do next (browser tools). Nothing essential for correct invocation is missing.

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?

Zero parameters, so there is no per-parameter meaning to add; the baseline of 4 applies. The description usefully implies where the actual inputs live, namely the appointment details gathered during the browser step, rather than in this call.

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 ('Create appointment in the user's own Fresha account') and immediately clarifies the actual output is step-by-step instructions rather than an executed booking. It does not explicitly name or route away from lookalike siblings such as create_appointment or fresha_reschedule_appointment, so differentiation is implied by scope rather than stated.

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 context plus a concrete follow-up path: use cotlet_browser_* tools inside the user's Fresha Cloud Browser to actually perform the steps. It stops short of stating when NOT to use this tool (e.g., when a direct booking sibling applies), so there are no explicit exclusions.

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