What problem does it solve? Writing Scenic scenarios by hand is error-prone: illegal asserts on random values, missing containment waivers for pedestrians, mismatched map parameters, and blueprint ids that do not exist in the build all cause failures that surface late and read like scenario bugs. This Skill turns a natural-language traffic description into a spec, generates a .scenic file from idioms proven on the local build, and validates it by compiling and sampling before any simulator is involved. ## Core Features & Use Cases - Spec-driven generation: scaffold_scenic.py converts a JSON spec (map, placement, ego, actors, relations) into a complete .scenic file using proven placement idioms like lane-section neighbour selection and conflicting-maneuver geometry. - Compile-and-sample validation: every generated file is compiled and sampled automatically, with verdicts (COMPILE-FAIL, SAMPLE-FAIL, PASS) mapped to concrete fixes. - Blueprint verification: blueprint_table.py diffs the CARLA build's content JSONs against Scenic's version-keyed table so scenarios only reference spawnable ids. - Use Case: Ask for "a pedestrian steps into the road ahead of the ego" and receive a validated .scenic file using CrossingBehavior with regionContainedIn waived, ready to simulate with the run-scenic-scenario skill. ## Quick Start Ask the agent to write a Scenic scenario where a car cuts in from the right lane on Town05 and validate that it compiles and samples.