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

With no annotations at all, the description carries the full behavioral burden, and it does add one genuinely useful fact: in-flight runs stop between steps rather than instantly, so cancellation is cooperative/graceful. It omits other key traits such as irreversibility, permission requirements, error behavior for completed runs, and the response shape.

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 front-loaded sentence with the core action first and the operational nuance in parentheses. No filler or redundant restatement of the tool name.

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 two-identifier cancellation tool, the description covers what it does and one behavioral nuance, which is the minimum viable. Given no annotations, no output schema, and zero parameter documentation, an agent still lacks confirmation of side effects, idempotency, and error cases.

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?

Both parameters (workflow_id, run_id) have 0% schema description coverage, and the description says nothing about them. It does not clarify whether workflow_id must be supplied alongside run_id, whether run_id is globally unique, or what identifier formats are accepted, so it fails to compensate for the coverage gap.

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 (a run), plus the eligible states 'running or waiting'. It does not distinguish itself from the sibling pipeline_run_cancel, so purpose is clear but sibling differentiation is left to the agent.

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?

The phrase 'running or waiting run' implicitly scopes when the tool applies (only non-terminal runs), which is a usable precondition. However, there is no explicit when-not guidance, no statement of what happens if the run already finished, and no pointer to pipeline_run_cancel as the alternative.

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