state-probinglisted

# State Probing > Status: v0.1 baseline draft — derived from the case catalog and axis definitions; awaiting trace evidence from Fable 5.1 case runs. ## When to apply - You are about to run a command, edit a file, or report a result whose correctness depends on the state of the environment (which version is installed, whether a process is up, what branch you are on). - A step failed in a way that only makes sense if reality differs from your assumption ("but I installed it"). - You resumed a session, a build ran, or time passed — any earlier probe result may now be stale. - You are inferring environment state from source, config, or memory instead of from the live system. - You are about to claim something *is* true of the world ("the server is running", "the file exists", "we're on main") rather than something you *did*. - The plan's next action is destructive or expensive and assumes a precondition you have not confirmed. ## Core loop 1. **Name the assumption as a checkable proposition.** Turn the vague belief into one testable claim about the world: "node is v20", "port 5173 is listening", "the working tree is clean", "`.env` contains `API_KEY`". If you cannot phrase it as something a single command could confirm or deny, it is not yet a probe target — sharpen it first. 2. **Pick the cheapest probe that discriminates.** Choose the command whose output *distinguishes* the assumption from its negation with the least cost and least side effect. `node