Cancel SMS Campaign

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

Annotations already declare destructiveHint=true and idempotentHint=false, so the description is not required to establish danger. It adds real context beyond them: which states permit cancellation and the important caveat that already-delivered messages remain delivered, i.e. cancellation is only partially reversible. It does not describe what happens if the campaign is in another state (error vs no-op), which is the main remaining gap.

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?

Three short sentences, front-loaded with the action and its gating condition, followed by the irreversible side effect and then the safety instruction. No filler.

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 single-parameter destructive mutation with no output schema, the description covers the precondition, the partial-irreversibility caveat, and the confirmation requirement. The only missing piece is behavior on invalid state or nonexistent campaign, a minor gap given annotations already flag destructiveness.

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?

There is a single `id` parameter with 100% schema description coverage including a UUID pattern, so the schema carries the semantics. The description only refers to it obliquely as 'the campaign' and adds no format or lookup guidance, so baseline 3 applies.

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 (cancel) and resource (SMS campaign) plus the exact lifecycle states in which cancellation is valid. An agent can tell this apart from send-sms-campaign or cancel-email-campaign without opening any schema.

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 precondition for use (`scheduled`, `queued` or `sending`) and a procedural rule (confirm with the user, naming the campaign). It does not name alternatives such as rescheduling via update-sms-campaign when a campaign is in a non-cancellable state, so it stops short of full when-not guidance.

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