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

Annotations only declare readOnlyHint=true; the description adds substantial semantics the annotation cannot convey — that the first target set applies to everyone while later sets are selected by what the customer's site signed about the user, that `paused` marks sets the plan has no room for, and that `available` is false below Pro. That is real behavioral context about what the returned state means, not a restatement of the annotation.

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 resource is front-loaded and every clause carries meaning — no filler. It is dense and somewhat run-on, packing four concepts into nested parentheticals, but the length is justified because no output schema exists to carry the field definitions.

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 and no parameters, the description is the only carrier of the return shape, and it covers it thoroughly: time zone, open days with encoding, round-the-clock behavior, priority target sets with selection rules, plan-gated unavailability, and the top-level availability flag. Nothing an agent needs to interpret the result 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 the baseline is 4. The description uses the space instead to explain the response fields an agent will encounter (`day` 0 = Monday, `from`/`to` in minutes after midnight, empty days = round the clock), which is the useful analogue of parameter semantics here.

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 precisely names the resource — the workspace's working hours, time zone, open days, and per-priority reply-time target sets — so an agent knows exactly what data comes back. It never states an explicit verb ('returns'/'retrieves') and does not name set_reply_times as its write counterpart, so differentiation from the sibling is left to inference from the readOnly annotation.

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?

There is no explicit 'use this when' sentence and no mention of set_reply_times as the tool for modifying the same settings. Usage is only implied: field-level detail (`paused`, `available`, priority target sets) makes it clear this is the read side of reply-time configuration, but an agent must infer that on its own.

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