Treat LLM function calls as proposals—validate, execute, then commit

Treat function calls from a model as proposals, not granted permissions. The verified sequence I recommend: the model proposes a JSON-shaped tool call; your app parses the outer wrapper and validates function name and argument schema; the app executes the registered tool implementation; and only after a verified success does the app commit the change to UI state. The article’s small in-memory fixture separates responsibilities so you can unit-test the ordering that matters: parseToolCall → validateFunctionCall → runToolBoundaryWorkflow → commit. That split makes it possible to assert distinct