DRC repair is one of the last serial bottlenecks in physical design that still requires a senior engineer in the loop. A violation fires, the engineer reads the geometry, makes an edit, reruns Calibre, and the cycle repeats until clean or until tapeout pressure wins. DRC-Aid puts an LLM inside that loop instead. The system converts each Calibre-reported violation into a bounded menu of legal geometric edits via a deterministic rule engine, uses an LLM to select among them given local layout context, and runs Calibre nmDRC/nmLVS immediately after each edit to verify compliance and prevent electrical-topology degradation. A global memory bank blocks the agent from revisiting repairs it has already tried. Evaluated on FreePDK45 layouts, DRC-Aid achieves DRC-clean, LVS-equivalent repairs in 92.5% of cases with 98% total violation reduction.
The architecture matters more than the headline number. The LLM is not generating free-form layout edits; it is selecting from a constrained menu that the rule engine guarantees is geometrically legal. Calibre runs after every move, not at the end of a batch. That loop structure is what separates this from prior LLM-EDA work that deferred verification to the end and accumulated unchecked errors. On cases with six or more violations, the LLM-selection policy outperforms random (54.4%) and deterministic-heuristic (83.3%) policies by widening margin, which is the direction you need: the hard cases get harder as node pitch shrinks, and that is exactly where a heuristic runs out of tokens.
The constraint being removed is not DRC expertise. Calibre still does the checking. What DRC-Aid removes is the human-latency cost of each fix-then-verify cycle, which in practice adds days to the tapeout schedule when violations are numerous or the layout is dense. The teams that lose if this approach matures are staffing models that treat senior physical design engineers as DRC-repair headcount during closing. The winning move is to evaluate DRC-Aid on internal PDKs now, before it becomes a vendor product with a licensing premium attached.