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

Annotations already declare this is a non-readonly, idempotent, non-destructive, non-open-world operation, so the bar is lower. The description adds genuine context beyond that: the action targets the caller's own clock and restarts working-time accrual, which explains the state effect the annotations cannot express.

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 clause-front-loaded sentence with no filler. The action and its consequence are stated in the first few words, and every part of the sentence carries meaning.

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 state toggle this is nearly sufficient; the annotations carry the safety profile. The one gap is failure behavior — it does not say what happens if no break is currently running — but that is minor for this tool's simplicity.

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 is 4. The description correctly implies no input is needed by scoping the action to 'the user's own' clock.

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 a specific action and resource — resuming the user's own time clock after a break — which is more precise than the title alone. It is distinguishable from startBreak by the explicit 'after a break' framing, though it never names the sibling directly.

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?

Usage is implied by 'after a break', which tells an agent the precondition, but there is no explicit statement of when not to call it or what to use instead if no break is active. Nothing routes the agent between this and startBreak/clockOut beyond the obvious pairing.

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