pcb-library

name	pcb-library
model	claude-opus-4-7
description	Footprint library management — search, list, inspect footprint details (KiCAD MCP tools 32-35)
disable-model-invocation	true
allowed-tools	Bash, Read, Grep, Glob, WebSearch, WebFetch
argument-hint	["list | search <query> | info <footprint> | pads <footprint>"]

Footprint Library Management

Map KiCAD MCP library tools to our project's custom footprint infrastructure and the KiCad CLI.

Overview

Footprints are defined procedurally in scripts/generate_pcb/footprints.py. Each footprint is a Python function that returns a list of pad S-expression strings for embedding inside a (footprint ...) block. Coordinates are relative to the footprint origin (center).

Pad dimensions are sourced from:

• KiCad 10 standard library footprints (RF_Module, Package_SO, etc.)
• JLCPCB/EasyEDA official component library (C91145, C318884, etc.)
• Manufacturer datasheets (Espressif, HCTL, Korean Hroparts Elec)

Steps

1. Depending on the argument:

   • list: Show all registered footprints from our custom library:

     cd /Users/pierrejonnycau/Documents/WORKS/esp32-emu-turbo && python3 -c "
     import inspect
     from scripts.generate_pcb import footprints as FP
     funcs = [name for name, obj in inspect.getmembers(FP) if inspect.isfunction(obj) and not name.startswith('_')]
     for f in sorted(funcs):
         print(f)
     "
     

   • search <query>: Search the KiCad official footprint library:

     kicad-cli fp search "<query>"
     

     Or use WebSearch for datasheets and JLCPCB part footprints.

   • info <footprint>: Show pad count, dimensions, and pin assignments for a custom footprint:

     cd /Users/pierrejonnycau/Documents/WORKS/esp32-emu-turbo && python3 -c "
     from scripts.generate_pcb import footprints as FP
     pads = FP.<footprint_function>()
     print(f'Pad count: {len(pads)}')
     for p in pads:
         print(p.strip())
     "
     

   • pads <footprint>: List all pad positions, sizes, and layers for a footprint. Use pad_positions.py utilities:

     cd /Users/pierrejonnycau/Documents/WORKS/esp32-emu-turbo && python3 -c "
     from scripts.generate_pcb.pad_positions import get_all_pad_positions, get_pad
     pads = get_all_pad_positions()
     # Show pads for a specific reference designator:
     for pad_num in range(1, 10):
         try:
             x, y = get_pad(pads, '<REF>', str(pad_num))
             print(f'Pad {pad_num}: ({x:.2f}, {y:.2f})')
         except:
             break
     "
     

2. For custom footprints: Read scripts/generate_pcb/footprints.py

3. For KiCad library footprints: Use kicad-cli fp list or kicad-cli fp search

Key Files

File	Purpose
scripts/generate_pcb/footprints.py	All custom footprint definitions (pad geometry, pin assignments)
scripts/generate_pcb/pad_positions.py	Pad position utilities: get_all_pad_positions(), get_pad(), esp32_gpio_pos(), fpc_pin_pos()
scripts/generate_pcb/primitives.py	Low-level pad helper used by footprints

Footprint Helpers in footprints.py

• _pad(num, typ, shape, x, y, w, h, layers, net, drill) -- Generate a single KiCad pad S-expression
• _smd(num, x, y, w, h, layer) -- Shorthand for SMD rectangular pad
• _fp_line(x1, y1, x2, y2, layer, width) -- Footprint-local silkscreen/fab line
• _fp_circle(cx, cy, r, layer, width) -- Footprint-local circle (pin 1 marker)
• Layer constants: SMD_F (front), SMD_B (back), THT (through-hole)

MCP Tool Mapping

MCP Tool	Our Implementation
list_libraries	kicad-cli fp list --libraries (KiCad official) + list functions in footprints.py (custom)
search_footprints	kicad-cli fp search <query> + grep through footprints.py
list_library_footprints	kicad-cli fp list <library>
get_footprint_info	Read footprint generator function from footprints.py and inspect pad output

Important Notes

• Our project uses custom procedural footprint generators, not KiCad library .kicad_mod files.
• Each footprint function returns a list of pad S-expression strings, not a complete footprint file.
• The footprints are embedded directly into the PCB file during generation by board.py.
• To add a new footprint: create a new function in footprints.py following the existing pattern, then reference it in board.py's _component_placeholders().