stop_runStops a running run early and leaves finished runs unchanged; the run cannot be resumed afterward.
stop run
Stop a run early. Works for every run type. Already-finished runs are left untouched; the response is the run either way.
Workflow: Stops a running run. The run cannot be resumed after stopping.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | The run id (run_...) |
Changes observed during successful MCP inspections.
v0.3.5Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true, idempotentHint=false and readOnlyHint=false, but the description adds genuinely new behavioral facts: the stop is irreversible ('cannot be resumed after stopping'), finished runs are unaffected, and the response is the run object either way. That last point substitutes for the missing output schema, which is real added value.
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?
The core facts are front-loaded, but the tool name is restated three times ('stop run', 'Stop a run early', '**Workflow:** Stops a running run'), so a meaningful fraction of a short description is redundant. The irreversibility note is well placed.
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 mutation tool whose annotations already flag destructiveness, the description covers the irreversibility, the no-op case, and the return shape. Nothing an agent needs in order 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?
Only one parameter, fully documented in the schema ('The run id (run_...)'), and the description adds nothing about id format or sourcing. With 100% schema coverage 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?
States a specific verb and resource ('Stop a run early') and explicitly scopes it to every run type, which is enough to separate it from siblings like get_run or list_runs. It does not name any sibling it must not be confused with, so it falls short of a 5.
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 description implies when to use it (a run is currently running) and clarifies what happens if the run already finished ('left untouched'). However, it never names an alternative such as get_run to check status first, nor does it state prerequisites or exclusions explicitly.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.