Write or revise hardware product requirements (product/README.md, product/requirements.json, product/contract.json). Use at the start of any hardware product design before parts selection.

Hardware product pipeline orchestrator (PRD → BOM → PCB → CAD → fabrication). Use FIRST for any request to design a hardware product, electronic device, PCB, or enclosure end-to-end. Routes to replicator-prd, replicator-parts, replicator-pcb, replicator-cad.

Design PCBs as code with tscircuit (React/TSX) and the tsci CLI - schematic, layout, DRC, Gerber/BOM/CPL export for JLCPCB fabrication. Use after the BOM stage when the product needs a custom PCB.

Select electronic components and build a procurement-ready BOM with real LCSC/JLC supplier evidence (stock, price, datasheet). Use after the PRD stage and before PCB design. Provides parts_search.py (jlcsearch API) and bom_validate.py (schema gate).

Parametric CAD modeling with build123d (Python) - enclosures, mechanical parts, assemblies. Builds a scene from cad/parts/*.py, exports STEP/GLB, renders PNG views for visual self-review, and prepares STL/3MF for printing. Use after PCB release (or directly for non-PCB products).

Explicit advanced workflow for generating, inspecting, dry-running, and validating plain FDM `.gcode` with real slicer CLIs. Use only when the user asks Replicator to generate G-code, needs headless/reproducible slicing, or cannot use a slicer UI.

Explicit advanced workflow to inspect status, upload, or cautiously start/control local Bambu Lab printers through LAN FTPS/MQTT after validated G-code exists. Use only when the user asks for printer communication or physical print control.

Use before Project Replicator product, hardware, PCB, CAD, manufacturing, or review work.

Use before Project Replicator PCB source, layout, routing, DRC, fabrication, or PCB visual-review work.

Use when writing or revising product/README.md, product/requirements.json, or product/contract.json in project-replicator.

Use when uploaded or project PDF files need exact text extraction, page-specific review, visual inspection of embedded images/diagrams/scans, datasheet figures, tables, or layout-sensitive evidence.

Independently audit one immutable, Host-frozen PCB release candidate using the design's own editable source, its manufacturing reports, and board-frame measurements from `pcb.measure`. Use only for the Host-owned PCB release review that returns a prioritized Markdown report; do not use for PCB editing, routing, or fabrication export.

Use for persistent, visual, short-loop CAD modeling with cad.open, cad.add_part, cad.edit_part, cad.place, cad.import, cad.delete, cad.look, cad.inspect, Host-owned CAD Review, and cad.export.

Independently audit one complete committed CAD build using cad.look image evidence and cad.inspect geometry facts. Use only for the Host-owned CAD handoff review that returns prioritized P0/P1 issues as ordinary text; do not use for CAD editing, finite-element analysis, physical load certification, or export.

Use for CAD Part Research when standard, purchasable, or library-backed mechanical components must be resolved before modeling.

Use when standard mechanical parts, fasteners, bearings, V-slot rails, T-nuts, wheels, or linear-motion parts are needed in Build123d CAD, and always before modeling a screw into a 3D-printed part — printed screw joints must come from this skill's kit, never hand-modeled.

Use when custom Build123d Python CAD code, geometry operations, selectors, locations, joints, assemblies, imports, exports, or DFM details are needed. Read `references/dfm-rules.md` BEFORE writing the first line of geometry code for any screw boss, standoff, snap fit, wall interface, or overhang-sensitive feature — not after the shape exists. A screw fastening into a 3D-printed part additionally requires the `build123d-libs` kit; never hand-model that joint.

Prepare committed Replicator CAD objects for ordinary FDM printing by arranging quantities across real build-plate dimensions and exporting one standard unsliced `.3mf` per plate for Bambu Studio or another slicer.

Use when electronic components must be selected, priced, checked for stock, compared with alternatives, or prepared as BOM-ready candidates with datasheet-backed implementation evidence.

Use when a selected electronic parts list must be validated, enriched, exported, or made procurement-ready.