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

Adds real behavior beyond the lone readOnlyHint=false annotation: the pause 'freezes the clock' and 'validity extends if the plan allows', which signals a conditional side effect, and it flags the preview/confirm gate. It omits what happens to sessions or check-ins scheduled inside the pause window.

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?

Two compact clauses, no filler, with the core action front-loaded before the behavioral caveat and the confirm-gate. Nothing could be removed without losing information.

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 nested-object mutation with no output schema and only a readOnlyHint annotation, the description covers the confirm gate and the conditional validity extension but leaves out prerequisites, idempotency, and the effect on scheduled sessions. Adequate to attempt the call, not complete.

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?

Schema coverage is 50%; startAt carries an ISO-date example and endAt refs it, but subscriptionId and reason have no description anywhere. The description's 'between two dates' maps to startAt/endAt but it says nothing about what 'reason' is for or where subscriptionId comes from, so the gap is not compensated.

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 ('Pause a client's membership') plus the scope ('between two dates'), which is enough to identify the operation. It does not distinguish itself from the sibling end_membership_pause, so an agent must infer the boundary between the two.

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 rather than stated: the confirm-gating note tells the agent how to invoke it, but nothing says when to pause versus call end_membership_pause or cancel_client_subscription, nor what preconditions (active membership, valid date range) apply.

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