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

readOnlyHint=true already tells the agent this is a safe read. The description adds that the scope is 'the coach's' schedules (implicitly the authenticated coach's own clients) and what data each schedule carries, but says nothing about ordering, volume, or whether inactive schedules are included.

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?

A single compact sentence with no filler, giving the resource and its key fields up front. It is arguably too terse, but nothing in it is wasted.

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, read-only list tool with no output schema, the description covers both what is returned and at what granularity (one schedule per client with weekday, time, questions). Only the scoping/edge-case details (inactive schedules, ordering) are absent, which is minor here.

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 there is nothing for the description to disambiguate; baseline 4 applies. The mention of 'per client' usefully clarifies the grouping of the returned data even without filter parameters.

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 names the specific resource — the coach's recurring check-in schedules — and enumerates its shape (weekday + time + questions per client), which distinguishes it from the check-in log siblings (list_checkins, get_checkin_logs). It is phrased as a noun fragment rather than a verb+resource, but the 'list_' name plus the resource description leaves little ambiguity.

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?

No guidance on when to retrieve schedules versus related tools such as list_checkins, get_checkin, or upsert_checkin_schedule / delete_checkin_schedule / schedule_checkin. The agent must infer usage purely from the name.

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