operation_cancel

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

Annotations only declare readOnlyHint=false and destructiveHint=false, so the description carries the real burden and does so well: it discloses state-dependent outcomes per operation type and warns that kill=true terminates PowerView and loses target state. There is mild tension with destructiveHint=false given the opt-in kill path, but the default path (kill=false) is genuinely non-destructive, so this reads as under-specification rather than contradiction.

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 dense sentences, front-loaded with the core action before the state breakdown and the danger warning. The telegraphic style ("a run stops waiting and leaves the target running") is efficient but slightly compressed and open to misreading.

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-parameter control tool with no output schema, the description covers the important unknowns: what cancellation means per state and the cost of the kill path. It does not say what the call returns or whether the cancellation is reversible, which an agent might want before invoking it.

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 100% and the schema already explains that kill terminates PowerView and loses target state, so the description largely restates it. The one addition is the necessity qualifier ("can only be ended with kill=true"), which is useful but modest; baseline 3 is appropriate.

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 ("Cancel an operation") and immediately differentiates by operation state — queued operations are dropped, scripts are stopped, runs stop waiting. This lets an agent distinguish it from operation_get, though it never names a sibling explicitly.

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?

"A blocked command can only be ended with kill=true" gives an explicit conditional for the non-obvious path, which is exactly the guidance an agent needs. It stops short of saying when not to cancel or whether to inspect the operation with operation_get first.

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