Cancel a running research backtest by ID, stopping only the Backtester job while leaving brokerage orders untouched.
Cancel a running research backtest. This affects only the Backtester job and never a brokerage order.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Backtest ID returned by tastytrade. |
Changes observed during successful MCP inspections.
v0.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. The description clarifies the scope (only backtest jobs, not orders), which is critical behavioral context. However, it does not mention side effects such as whether the cancellation is irreversible or if resources are freed, but given the tool is a cancellation, the key transparency is the scope distinction, which is well covered.
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 description is a single sentence that is concise and front-loaded with the core purpose ('Cancel a running research backtest'), followed by an important clarification. There is zero waste.
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 simple cancel operation with one well-documented parameter, the description effectively covers the core usage. The only minor gap is not specifying what happens after cancellation (e.g., no return value description), but given the lack of output schema and the simplicity, it is reasonably complete.
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?
The schema has 100% coverage for the single parameter, describing it as 'Backtest ID returned by tastytrade.' The description does not add extra semantics beyond the schema, but since the schema is complete, the baseline of 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?
The description clearly states the verb (cancel), the resource (a running research backtest), and explicitly distinguishes it from brokerage orders. This makes it unambiguous and differentiates it from sibling tools like tastytrade_list_backtests or tastytrade_create_backtest.
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 explicitly states when to use this tool (to cancel a running backtest) and what it does NOT affect (never a brokerage order). This is a clear 'when/not' guideline, which is particularly important given the presence of tastytrade_simulate_trade and other order-related tools in the sibling list.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.