LangChain and CrewAI#

Wrap the function that actually performs the effect. Telemetry callbacks that only record a denied decision do not prevent the function from running.

Availability#

These adapters use structural interfaces without importing LangChain or CrewAI. Check the framework's dispatch lifecycle in your application.

TypeScript wrapping#

wrapLangChainTool(tool, guard) gates invoke, call, and func and preserves the tool's prototype and fields. The returned proxy enforces before calling the original method. The callback handler asks the framework to raise errors and await handlers; verify that your selected executor respects both.

Run adapters.mjs as described in the structural adapter test. A blocked tool's asynchronous handler is never called.

Python argument mapping#

For the default tool_call action, decorators measure the actual bound positional/keyword arguments and use the configured tool name. For another action type, pass action_mapper(args, kwargs) returning an EvaluationAction with the correct type and a nonempty target. Do not infer filesystem authority from a Python function's name.

Download adapters.py and use the Python SDK setup. Run python adapters.py policy.yaml. The test covers both decorators, a protected-path mapper, and refusal when a non-tool action lacks a mapper. The dispatch list remains empty on every refusal.

Lifecycle and error handling#

Let HushSpecDenied stop the call. Do not catch it and then execute the same handler as a fallback. Preserve a useful model-facing refusal and retain the operator's evidence. Close a watching Python guard when the application stops; stop TypeScript providers separately.

Warnings need affirmative confirmation, and custom callbacks must obey the same-guard non-reentrancy contract. A framework wrapper does not mediate effects performed elsewhere in the process.