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

Annotations already declare readOnlyHint=false and destructiveHint=false, so the description's main contribution is disclosing the queue-clearing side effect, which the agent could not have guessed from the name. That is real added value. However, it leaves open what happens to partially completed action state and whether the cleared queue is recoverable – and 'clear your queue' sits in mild tension with destructiveHint=false, though cancellation is defensibly non-destructive.

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?

One sentence, front-loaded with the primary effect and zero filler. Every word carries weight and nothing is buried.

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?

The tool is simple and annotations carry the safety profile, and there is no output schema to explain. But for a cancellation tool the agent still needs to know whether the stop is immediate or graceful, and whether any result of the cancelled action is returned, neither of which is addressed in a single short sentence.

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 optional api_key parameter with 100% schema description coverage, so the schema fully documents it and the description adds nothing further. Baseline 3 applies when structured fields do the work. The description also fails to clarify that the tool is callable with no arguments at all, which is notable given zero required parameters.

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 object: 'Stop your running action' plus the secondary effect 'clear your queue'. This is clearly distinguishable from siblings like wait, move, or attack, which all initiate or continue activity. It stops short of a 5 only because it never names the sibling it substitutes for in a blocked/queued scenario.

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 by 'your running action and your queue' – an agent can infer this is the escape hatch when it wants to abort work in flight. There is no explicit statement of when to prefer it over, say, waiting for the action to finish, and no note on prerequisites or whether the cancel is immediate.

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