Cancel workflow run

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

Annotations already declare destructiveHint=true and idempotentHint=true, but the description adds a genuinely non-derived consequence: 'Mail already sent cannot be recalled' — it scopes exactly what cancelling does and does not undo. It also states the return shape ('Confirmation of the cancellation'), which the absence of an output schema makes valuable.

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?

Four labeled blocks, each one sentence, front-loaded with purpose and then exclusions. No filler and every line carries distinct 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 2-parameter mutation with full schema coverage and no output schema, the description covers purpose, alternatives, trigger conditions, irreversibility, and return expectation. Nothing an agent needs to call it correctly 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?

Schema description coverage is 100% and both parameters (id as Workflow UUID, executionId as Execution UUID) are self-documented. The description adds no format or relationship guidance beyond the schema, so the baseline of 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?

The description gives a precise verb+resource+scope: 'Stop one contact's run of a workflow.' The 'Not for' line names the two confusable siblings (plunk_cancel_all_workflow_executions and plunk_update_workflow), so an agent can disambiguate the singular-vs-global-vs-config distinction 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?

Explicit when/when-not guidance: the 'Not for' section routes to the two alternative tools, and 'Use when' enumerates concrete triggers (replied, unsubscribed, entered by mistake). Nothing about tool selection is left to inference.

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