kicad-tools

Tools for AI agents to work with KiCad projects.

🌐 Live demo gallery: kicad-tools.org — explore example boards built end-to-end by these tools, with 2D/3D renders, routing & manufacturing metrics, downloadable fabrication packages, and an interactive in-browser PCB viewer.

This project provides standalone Python tools that enable AI agents (LLMs, autonomous coding assistants, etc.) to parse, analyze, and manipulate KiCad schematic and PCB files programmatically. All tools output machine-readable JSON and require no running KiCad instance.

Why Agent-Focused?

Traditional EDA tools require GUIs and manual interaction. kicad-tools bridges the gap by providing:

Structured data access - Parse KiCad files into clean Python objects
Machine-readable output - All CLI commands support --format json
Programmatic modification - Edit schematics and PCBs without a GUI
LLM reasoning interface - Purpose-built module for LLM-driven PCB layout decisions

Whether you're building an AI assistant that reviews PCB designs, automating DRC checks in CI, or experimenting with LLM-driven routing, these tools provide the foundation.

Installation

# Base install (CPU only)
pip install kicad-tools

# With CUDA GPU acceleration (NVIDIA GPUs on Linux/Windows)
pip install kicad-tools[cuda]

# With Metal GPU acceleration (Apple Silicon Macs)
pip install kicad-tools[metal]

# With native C++ router backend
pip install kicad-tools[native]

# With CMA-ES placement optimization (kct optimize-placement / kct build --optimize-placement)
pip install kicad-tools[placement]

# Everything (all optional dependencies)
pip install kicad-tools[all]

The placement extra pulls in cmaes (and, transitively, scipy). It is required by kct optimize-placement and the placement step of kct build --optimize-placement; without it those commands exit with a clear message naming the extra. The dev and all extras already include it, so uv sync --extra dev is sufficient for development.

To check GPU acceleration status:

kct calibrate --show-gpu

Quick Start

Command Line (`kct`)

# List symbols in a schematic
kct symbols project.kicad_sch
kct symbols project.kicad_sch --format json

# Trace nets
kct nets project.kicad_sch
kct nets project.kicad_sch --net VCC

# Generate bill of materials
kct bom project.kicad_sch
kct bom project.kicad_sch --format csv --group

# Run ERC (requires kicad-cli)
kct erc project.kicad_sch
kct erc project.kicad_sch --strict

# Run DRC with manufacturer rules
kct drc board.kicad_pcb
kct drc board.kicad_pcb --mfr jlcpcb
kct drc --compare  # Compare manufacturer rules

Python API

from kicad_tools import load_schematic, Schematic

# Load and parse a schematic
doc = load_schematic("project.kicad_sch")
sch = Schematic(doc)

# Access symbols
for symbol in sch.symbols:
    print(f"{symbol.reference}: {symbol.value}")

# Access hierarchy
for sheet in sch.sheets:
    print(f"Sheet: {sheet.name}")

PCB Autorouter

from kicad_tools.router import Autorouter, DesignRules

# Configure design rules
rules = DesignRules(
    grid_resolution=0.25,  # mm
    trace_width=0.2,  # mm
    clearance=0.15,  # mm
)

# Create router and add components
router = Autorouter(width=100, height=80, rules=rules)
router.add_component("U1", pads=[...])

# Route all nets
result = router.route_all()
print(f"Routed {result.routed_nets}/{result.total_nets} nets")

LLM-Driven PCB Layout

The reasoning module enables LLMs to make strategic PCB layout decisions while tools handle geometric execution:

from kicad_tools import PCBReasoningAgent

# Load board
agent = PCBReasoningAgent.from_pcb("board.kicad_pcb")

# Reasoning loop
while not agent.is_complete():
    # Get state as prompt for LLM
    prompt = agent.get_prompt()

    # Call your LLM (OpenAI, Anthropic, local, etc.)
    command = call_llm(prompt)

    # Execute and get feedback
    result, diagnosis = agent.execute(command)

# Save result
agent.save("board_routed.kicad_pcb")

CLI usage:

# Export state for external LLM
kct reason board.kicad_pcb --export-state

# Interactive mode
kct reason board.kicad_pcb --interactive

# Auto-route priority nets
kct reason board.kicad_pcb --auto-route

See examples/llm-routing/ for complete examples.

MCP Server for AI Agents

Enable AI assistants like Claude to interact with KiCad designs via the Model Context Protocol:

# Install with MCP support
pip install "kicad-tools[mcp]"

# Run the MCP server
kct mcp serve

Configure Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json):

{
  "mcpServers": {
    "kicad-tools": {
      "command": "python",
      "args": ["-m", "kicad_tools.mcp.server"]
    }
  }
}

Available MCP tools:

Analysis: analyze_board, get_drc_violations, measure_clearance
Export: export_gerbers, export_bom, export_assembly
Placement: placement_analyze, placement_suggestions
Sessions: start_session, query_move, apply_move, commit, rollback
Routing: route_net, route_net_auto, get_unrouted_nets
Optimization: optimize_placement, evaluate_placement

See docs/mcp/ for complete documentation.

Circuit Blocks

Build schematics using reusable, tested circuit blocks:

from kicad_tools.schematic.models import Schematic
from kicad_tools.schematic.blocks import (
    MCUBlock,
    CrystalOscillator,
    LDOBlock,
    USBConnector,
    DebugHeader,
    I2CPullups,
    ResetButton,
)

sch = Schematic("My STM32 Design")

# Add an MCU with bypass capacitors
mcu = MCUBlock(
    sch, x=150, y=100, part="STM32F103C8T6", bypass_caps=["100nF", "100nF", "100nF", "4.7uF"]
)

# Add crystal oscillator
xtal = CrystalOscillator(sch, x=100, y=100, frequency="8MHz", load_caps="20pF")

# Add power supply
ldo = LDOBlock(sch, x=50, y=100, input_voltage=5.0, output_voltage=3.3)

# Add USB connector with ESD protection
usb = USBConnector(sch, x=50, y=150, connector_type="type-c", esd_protection=True)

# Add debug header for programming
debug = DebugHeader(sch, x=200, y=100, interface="swd")

# Add I2C pull-ups
i2c = I2CPullups(sch, x=180, y=150, pullup_value="4.7k")

# Add reset button with debounce
reset = ResetButton(sch, x=120, y=50, debounce_cap="100nF")

# Connect via ports
sch.add_wire(ldo.port("VOUT"), mcu.port("VDD"))
sch.add_wire(xtal.port("OUT"), mcu.port("OSC_IN"))

sch.save()

Available blocks:

MCUBlock: Microcontroller with bypass capacitors
CrystalOscillator: Crystal/oscillator with load capacitors
LDOBlock: Linear regulator with input/output capacitors
USBConnector: USB-B/Mini/Micro/Type-C with optional ESD protection
DebugHeader: SWD/JTAG/Tag-Connect programming headers
I2CPullups: I2C bus pull-up resistors with optional filtering
ResetButton: Reset switch with debounce capacitor
BarrelJackInput/USBPowerInput/BatteryInput: Power input circuits
LEDIndicator: Status LED with current-limiting resistor
DecouplingCaps: Decoupling capacitor placement

See boards/04-stm32-devboard/ for a complete design example.

Project Workflow

Work with complete KiCad projects using the unified Project class:

from kicad_tools import Project

# Load a KiCad project
project = Project.load("myboard.kicad_pro")

# Cross-reference schematic to PCB
result = project.cross_reference()
print(f"Unplaced components: {result.unplaced}")

# Export manufacturing files
project.export_assembly("output/", manufacturer="jlcpcb")

Progress Callbacks

Monitor long-running operations with progress callbacks:

from kicad_tools import ProgressCallback, ProgressContext
from kicad_tools.router import Autorouter


def on_progress(progress: float, message: str, cancelable: bool) -> bool:
    print(f"{progress * 100:.0f}%: {message}")
    return True  # Return False to cancel


# Use with context manager
with ProgressContext(on_progress):
    router = Autorouter(...)
    router.route_all()  # Progress reported automatically

# Or create JSON-formatted callbacks for automation
from kicad_tools import create_json_callback

callback = create_json_callback()

Parametric Footprint Generators

Create KiCad footprints programmatically with IPC-7351 naming:

from kicad_tools.library import create_soic, create_qfp, create_chip

# Generate SOIC-8 footprint
fp = create_soic(pins=8, pitch=1.27)
fp.save("SOIC-8.kicad_mod")

# Generate LQFP-48
fp = create_qfp(pins=48, pitch=0.5, body_size=7.0)
fp.save("LQFP-48.kicad_mod")

# Generate 0402 chip resistor
fp = create_chip("0402", prefix="R")
fp.save("R_0402.kicad_mod")

Available generators: create_soic, create_qfp, create_qfn, create_sot, create_chip, create_dip, create_pin_header.

Symbol Library Management

Create and edit KiCad symbol libraries programmatically:

from kicad_tools.schema.library import SymbolLibrary

# Create a new symbol library
lib = SymbolLibrary.create("myproject.kicad_sym")

# Create a symbol with pins
sym = lib.create_symbol("MyPart")
sym.add_pin("1", "VCC", "power_in", (0, 5.08))
sym.add_pin("2", "GND", "power_in", (0, -5.08))
sym.add_pin("3", "IN", "input", (-7.62, 0))
sym.add_pin("4", "OUT", "output", (7.62, 0))

# Save the library
lib.save()

# Load and edit existing library
lib = SymbolLibrary.load("existing.kicad_sym")

Pure Python DRC

Run design rule checks without requiring kicad-cli:

# Check against manufacturer rules
kct check board.kicad_pcb --mfr jlcpcb --format json

# Check with custom rules
kct check board.kicad_pcb --clearance 0.15 --trace-width 0.2

Python API:

from kicad_tools.schema.pcb import PCB
from kicad_tools.validate import DRCChecker

pcb = PCB.load("board.kicad_pcb")
checker = DRCChecker(pcb, manufacturer="jlcpcb")
results = checker.check_all()

print(results.summary())
for violation in results:
    print(f"  {violation.rule_id}: {violation.message}")

Placement Optimization

Optimize component placement using physics-based or evolutionary algorithms:

from kicad_tools.optim import PlacementOptimizer, EvolutionaryPlacementOptimizer
from kicad_tools.schema.pcb import PCB

pcb = PCB.load("board.kicad_pcb")

# Physics-based optimization (force-directed)
optimizer = PlacementOptimizer.from_pcb(pcb)
optimizer.run(iterations=1000, dt=0.01)

# Get optimized placements
for comp in optimizer.components:
    print(f"{comp.ref}: ({comp.x:.2f}, {comp.y:.2f}) @ {comp.rotation:.1f}°")

# Evolutionary optimization (genetic algorithm)
evo = EvolutionaryPlacementOptimizer.from_pcb(pcb)
best = evo.optimize(generations=100, population_size=50)

# Hybrid: evolutionary global search + physics refinement
physics_opt = evo.optimize_hybrid(generations=50)
physics_opt.write_to_pcb(pcb)
pcb.save("optimized.kicad_pcb")

CLI usage:

kct placement board.kicad_pcb --optimize --iterations 1000

Trace Optimization

Optimize routed traces for shorter paths and fewer vias:

from kicad_tools.router import TraceOptimizer
from kicad_tools.schema.pcb import PCB

pcb = PCB.load("board.kicad_pcb")
optimizer = TraceOptimizer(pcb)
optimizer.optimize()
pcb.save("optimized.kicad_pcb")

CLI usage:

kct optimize-traces board.kicad_pcb -o optimized.kicad_pcb

Datasheet Tools

Search, download, and parse component datasheets:

# Search for datasheets
kct datasheet search STM32F103C8T6

# Download a datasheet
kct datasheet download STM32F103C8T6 -o datasheets/

# Convert PDF to markdown
kct datasheet convert datasheet.pdf -o datasheet.md

# Extract pin tables
kct datasheet extract-pins datasheet.pdf

# Extract images and tables
kct datasheet extract-images datasheet.pdf -o images/
kct datasheet extract-tables datasheet.pdf

Python API:

from kicad_tools.datasheet import DatasheetManager, DatasheetParser

# Search and download
manager = DatasheetManager()
results = manager.search("STM32F103C8T6")
datasheet = manager.download(results[0])

# Parse PDF
parser = DatasheetParser("STM32F103.pdf")
markdown = parser.to_markdown()

# Extract images and tables
images = parser.extract_images()
tables = parser.extract_tables()
for table in tables:
    print(table.to_markdown())

Parts Lookup (LCSC / JLCPCB)

Look up LCSC part numbers, check BOM availability, and pull pricing/stock:

from kicad_tools.parts import LCSCClient

client = LCSCClient()
part = client.lookup("C2040")
if part:
    print(f"{part.mfr_part}: {part.stock} in stock, best ${part.best_price:.4f}")

Part lookups resolve through a tiered chain (each tier falls back to the next):

Local response cache — previously fetched parts.
Official JLCPCB open-platform API — only when you supply your own API key (see below). Off by default; inert without keys.
Anonymous scrape API — the public JLCPCB web endpoints (requires the parts extra: pip install "kicad-tools[parts]"). Note: as of July 2026 JLCPCB's public endpoint returns 404 — treat this tier as best-effort/deprecated and rely on tier 2 (BYO key) or tier 4 (offline).
Offline jlcparts catalog — a locally synced mirror (kct parts sync-catalog, ~620 MB download, ~5 GB on disk, ~7.1 M components), usable fully offline.

Using your own JLCPCB API key

kicad-tools can talk to the official JLCPCB open-platform API using credentials you register yourself at the JLCPCB developer portal (https://jlcpcb.com/ → developer/open platform). This is strictly opt-in: you bring your own key, kicad-tools ships only the signed client. Without keys, behavior is unchanged — the official tier is simply skipped.

Set all three environment variables (kicad-tools reads them via os.environ; it does not load a .env file itself, so use your shell, direnv, or a dotenv runner — see .env.example):

export JLCPCB_APP_ID="your-app-id"
export JLCPCB_ACCESS_KEY="your-access-key"
export JLCPCB_SECRET_KEY="your-secret-key"

All three must be set (and non-empty) to activate the official tier; if any is missing it stays inert. Once set, LCSCClient.lookup() / lookup_many() prefer the official API for part-detail-by-code, falling back down the chain above on any failure.

Notes and caveats:

What it unlocks: authenticated part detail lookup by LCSC code only. There is no confirmed official keyword/MPN search endpoint, so LCSCClient.search() always uses the anonymous/offline path even with keys.
IP whitelisting: the developer portal offers an IP-whitelist feature. If you enable it, your machine's public IP must be whitelisted or requests are rejected (surfaced as a distinct, actionable error).
Never commit credentials. .env is gitignored; the secret key is used only as HMAC key material and is never transmitted.
The request-signing scheme is not first-party-documented by JLCPCB; the client implements the best-available community-reverse-engineered variant for the Parts surface, with the two ambiguous parameters isolated as single flip-points in parts/jlcpcb_api.py (see that module and issue #4118).

CLI Commands

Unified CLI (`kct` or `kicad-tools`)

The commands below are the ones most workflows reach for. The authoritative full list (every command and subcommand) lives in CLI Reference → Commands Overview.

Inspection and validation

Command	Description
`kct symbols <schematic>`	List symbols with filtering
`kct nets <schematic>`	Trace and analyze nets
`kct bom <schematic>`	Generate bill of materials
`kct erc <schematic>`	Run electrical rules check
`kct drc <pcb>`	Run design rules check (requires kicad-cli)
`kct check <pcb>`	Pure Python DRC (no kicad-cli needed)
`kct creepage <pcb>`	HV surface-path (creepage) audit vs IEC 60664-1 / 62368-1
`kct creepage-export-rules <project>`	Export voltage-domain netclasses + pairwise HV clearance rules so kicad-cli DRC enforces creepage
`kct analyze <pcb>`	Signal-integrity, current-sense, and electrical-rating layout lint
`kct audit <project>`	Manufacturing readiness audit (ERC, DRC, connectivity, compatibility)
`kct impedance <subcommand>`	Transmission line impedance calculations

Layout and routing

Command	Description
`kct route <pcb>`	Autoroute a PCB (`--nets`/`--skip-nets` to select nets, `--complete` to finish one)
`kct route-auto <pcb>`	Orchestrator-based multi-strategy autorouting
`kct optimize-traces <pcb>`	Optimize routed traces
`kct placement <pcb>`	Detect and optimize component placement
`kct optimize-placement <pcb>`	CMA-ES/Bayesian global placement optimization
`kct zones <subcommand>`	Add copper pour zones (and `hv-keepout` plane voids)
`kct stitch <pcb>`	Auto-add stitching vias for plane connections
`kct reason <pcb>`	LLM-driven PCB layout reasoning

Repair

Command	Description
`kct fix-drc <pcb>`	Automated DRC violation repair (clearance + drill)
`kct fix-erc <schematic>`	Automated ERC violation repair (PWR_FLAG + no-connect)
`kct fix-vias <pcb>`	Fix vias to meet manufacturer specifications (incl. off-pad relocation)
`kct pipeline <input>`	End-to-end repair pipeline for existing PCBs

Parts and manufacturing

Command	Description
`kct datasheet <subcommand>`	Search, download, parse datasheets
`kct parts <subcommand>`	LCSC/JLCPCB part lookup, cache, offline catalog sync
`kct export <pcb>`	Manufacturing bundle export (gerbers, BOM, CPL)
`kct mfr <subcommand>`	Manufacturer rule profiles (apply-rules, validate)
`kct spec <subcommand>`	Project specification (`.kct`) management
`kct fleet status`	Routing + manufacturing readiness across all boards

Environment

Command	Description
`kct doctor`	Diagnose kicad-tools installation health (version-record drift)
`kct build-native`	Build the C++ router backend for 10-100x faster routing
`kct mcp serve`	Start MCP server for AI agent integration

All commands support --format json for machine-readable output.

PCB Tools

Command	Description
`kicad-pcb-query summary`	Board overview
`kicad-pcb-query footprints`	List footprints
`kicad-pcb-query nets`	List all nets
`kicad-pcb-query traces`	Trace statistics
`kicad-pcb-modify move`	Move component
`kicad-pcb-modify rotate`	Rotate component

Library Tools

Command	Description
`kicad-lib-symbols`	List symbols in library

Modules

Module	Description
`core`	S-expression parsing and file I/O
`schema`	Data models (Schematic, PCB, Symbol, Wire, Label)
`schematic.blocks`	Reusable circuit blocks (MCU, LDO, USB, debug headers, etc.)
`project`	Unified Project class for schematic+PCB workflows
`library`	Footprint generation and symbol library management
`drc`	Design Rule Check report parsing (kicad-cli output)
`validate`	Pure Python DRC checker (no kicad-cli needed)
`erc`	Electrical Rule Check report parsing
`manufacturers`	PCB fab profiles (JLCPCB, OSHPark, PCBWay, Seeed)
`operations`	Schematic operations (net tracing, symbol replacement)
`router`	A* PCB autorouter with trace optimization
`optim`	Placement optimization (physics-based, evolutionary)
`reasoning`	LLM-driven PCB layout with chain-of-thought reasoning
`progress`	Progress callbacks for long-running operations
`datasheet`	Datasheet search, download, and PDF parsing
`mcp`	MCP server for AI agent integration
`pcb.layout`	Layout preservation for PCB regeneration

What's New (v0.20.0, August 2026)

Recent additions an agent reading these docs cold should know about. Older entries live in CHANGELOG.md.

Search-time HV pairwise clearance in the lattice engine (v0.20.0) — with --voltage-map, the lattice router now avoids HV↔LV proximity during search instead of merely failing the post-route gate; KiCad keepout rule areas are honored too, with a per-net-class spatial_keepouts sidecar filter for declared HV-domain segregation.
kct sch tidy (v0.20.0) — headless autoplace of Reference/Value fields (bbox-relative, rotation/mirror-aware) with --refs, --threshold, --dry-run, and a strict cosmetic-only guarantee (netlist/BOM/ERC provably unchanged). Pairs with the new sch_fields advisory lint in kct check (sch_field_offset / sch_field_overlap).
kct net-status strict by default (v0.20.0) — connectivity now uses real copper geometry (kicad-cli semantics) instead of endpoint proximity, eliminating false opens on poured nets; --legacy-proximity restores the old model, and --strict --why now compose.
kct pcb add-3d-models --refresh (v0.20.0) — re-resolve and rewrite existing (model ...) refs in place through the current tier chain (library → variant → substitution → LCSC sidecar); default remains byte-identical insert-only.
Board-edge keepout auto-resolution (v0.20.0) — in-process routing via load_pcb_for_routing now derives the board-edge keepout from the manufacturer's min_edge_clearance automatically (explicit 0 opts out), matching what the CLI already did.
HV-isolation design loop (v0.19.0) — kct creepage --voltage-map derives each conductor pair's required creepage from its own |ΔV| instead of one group working voltage; kct zones hv-keepout generates plane voids so inner pours clear HV nets; kct optimize-placement --voltage-map / --hv-domains place HV parts with a hard creepage-keepout feasibility term. The /kct:hv-isolation-loop skill sequences the whole loop.
kct creepage-export-rules (since v0.19.0) — export voltage-domain netclasses plus pairwise HV clearance (rule ...) clauses into the project so kicad-cli pcb drc enforces creepage too, not just kct creepage.
kct check --emit-dru / --emit-drc-constraints (v0.19.0) — emit .kicad_dru / .kicad_pro sidecars from the checker's already-resolved --mfr floors, so kicad-cli pcb drc and kct check reason over identical rules by construction.
kct analyze electrical-rating (v0.19.0) — deterministic, advisory LED-overcurrent and capacitor voltage-derating checks sourced from schematic fields; parts missing ratings are skipped, never failed.
kct fix-vias off-pad relocation (v0.19.0) — relocate via-in-pad and plane-stitch vias off-pad while preserving connectivity, with THT hole-to-hole clearance checking and multi-branch relocation.
kct doctor (v0.19.0) — diagnose an installation's version-record drift (dependency pin, .kct/install-metadata.json, CLAUDE.md marker block). Advisory by default; --strict exits non-zero so it can gate CI.
kct route --complete (since v0.19.0) — targeted completion pass: detect the still-unconnected links and route only those, treating every other net's copper as a fixed obstacle. Implies --preserve-existing and never deletes copper; skip pour-carried nets with --complete-exclude-nets. See CLI Reference → route.
kct creepage HV audit + kct analyze current-sense (v0.18.0) — per-pair creepage census against IEC 60664-1 / 62368-1 tables (slot-aware, clearance and creepage reported as distinct values), and an analog lint for sense↔high-current parallel runs, sense-loop area, and Kelvin-tap integrity. A below-standard HV pair fails the kct audit gate.
Real --nets NET[,NET...] on route / route-auto (v0.18.0) — route only the listed nets (inverse of --skip-nets); non-listed copper is treated as a fixed obstacle.
Experimental routing substrates (v0.17.0) — --route-engine lattice (adaptive octilinear; 45°-legal copper by construction) and --route-engine mesh (constrained-Delaunay navmesh), both default off. --route-engine grid remains the default and is unchanged. See Routing Guide.
kct net-status --why (v0.17.0) — ranked fix recommendations explaining why each incomplete net is stuck, with pin-order-verified reversed-bundle detection.

Features

Pure Python parsing - No KiCad installation needed
Round-trip editing - Parse, modify, and save files preserving formatting
Full S-expression support - Handles all KiCad 8.0+ file formats
Schematic analysis - Symbols, wires, labels, hierarchy traversal
Circuit blocks - Reusable blocks for MCU, power, USB, debug headers, I2C, reset
PCB analysis - Footprints, nets, traces, vias, zones
Manufacturer rules - JLCPCB, PCBWay, OSHPark, Seeed design rules
PCB autorouter - A* pathfinding with net class awareness
Pure Python DRC - Design rule checking without kicad-cli
Placement optimization - Physics-based and evolutionary algorithms
Trace optimization - Path shortening and via reduction
Footprint generation - Parametric generators for common packages
Symbol library creation - Programmatic symbol creation and editing
Datasheet tools - Search, download, and PDF parsing
Progress callbacks - Monitor and cancel long-running operations
JSON output - Machine-readable output for automation

Requirements

Python 3.10+
numpy (for router module)
KiCad 8+ (optional) - for running ERC/DRC via kicad-cli

Development

This project uses uv for fast, reproducible Python environment management.

Quick Start

# Clone repository
git clone https://github.com/rjwalters/kicad-tools.git
cd kicad-tools

# Set up development environment (installs all dev dependencies)
uv sync --extra dev

# Build the C++ router backend (REQUIRED for production routing speed,
# delivers 10-100x A* speedup vs pure-Python; takes ~30s on first build,
# cached thereafter). uv sync does NOT build this — fresh checkouts and
# fresh worktrees need this step explicitly.
uv run kct build-native

# Verify the C++ backend is installed
uv run kct build-native --check
# Expected: "C++ backend: available (version 1.0.0)"

# Run tests
uv run pytest

# Run linter
uv run ruff check .

# Format code
uv run ruff format .

Routing performance note: Without the C++ backend, board routing falls back to pure-Python A* — typically 5-10x slower per net, which can push medium boards (e.g. board 07 in boards/07-matchgroup-test/) past the default 6-minute CI cap. If kct route appears stuck or per-net log lines take tens of seconds, run kct build-native --check first — a missing extension is the most common cause.

Fresh worktree checklist

Sync the lock-pinned dev environment first:
```
uv sync --frozen --extra dev
```
A fresh worktree performs no Python env setup, and a stale or drifted .venv/ (e.g. a mypy newer than the uv.lock pin) produces spurious mypy-baseline noise that looks like real type regressions (issue #4558). --frozen guarantees the resolved set matches uv.lock exactly — the same environment CI uses. Loom-created worktrees run this automatically via the .loom/hooks/post-worktree.sh hook; run it manually for hand-made worktrees or if the hook reported a failure.
Build the native extension. The worktree's .venv/ does not inherit the C++ extension built in the main checkout, and uv sync does not build it. After cd into the worktree, run uv run kct build-native once before any routing benchmarks.
If a local mypy error names a file outside your diff, rm -rf .mypy_cache and re-run before investigating it. .mypy_cache/ is gitignored, so it survives git reset --hard, git clean -fd, a rebase, and a worktree reuse — bare mypy / pnpm typecheck can replay an error computed against an older tree. CI is always cold (no actions/cache), so it will not reproduce the phantom. scripts/ci/check_mypy_baseline.py is already immune (it runs --no-incremental); see docs/contributing/development.md.

The build's nanobind dependency is composed into the default dev dependency-group, so a plain uv sync keeps it resolved and a later uv sync (e.g. adding --extra placement) will not prune it. If you installed with only a subset of groups, add the native extra explicitly so nanobind stays lockfile-tracked:

uv sync --extra native            # repo/dev worktree
pip install "kicad-tools[native]" # consumer / installed wheel

Avoid a bare pip install nanobind — it is not recorded in the resolved set and a subsequent uv sync will uninstall it, breaking the next kct build-native (issue #4412).

Available Commands

If you have pnpm installed, you can use these convenience scripts:

Command	Description
`pnpm setup`	Set up dev environment (`uv sync --extra dev`)
`pnpm test`	Run tests
`pnpm test:cov`	Run tests with coverage
`pnpm test:benchmark`	Run performance benchmarks
`pnpm lint`	Check code with ruff
`pnpm lint:fix`	Auto-fix lint issues
`pnpm format`	Format code with ruff
`pnpm format:check`	Check formatting
`pnpm typecheck`	Run mypy type checking
`pnpm check:ci`	Run full CI suite (format + lint + tests)

Direct uv Commands

# Run tests with coverage
uv run pytest --cov=kicad_tools --cov-report=term-missing

# Run benchmarks
uv run pytest tests/test_benchmarks.py --benchmark-only

# Type checking
uv run mypy src/

# Full CI check
uv run ruff format . --check && uv run ruff check . && uv run pytest

Agent Skills (`kct` namespace)

kicad-tools ships its own Claude agent skills under .claude/commands/kct/ (invoked as /kct:<name>), a harness-agnostic namespace kept separate from any installed orchestration framework. Seven skills ship today — /kct:tapeout (complete fab-ready export bundle or loud refusal), /kct:manufacturing-readiness (sign-off gates), /kct:hv-isolation-loop (mains/HV creepage design loop), /kct:board-recipe-scaffold, /kct:layout-journal, /kct:ee-review (advisory EE decision document for analog/placement-blocked boards), and /kct:help (introspective guide to the namespace). See .claude/commands/kct/README.md for the full contracts.

Related Projects

Zeo — A KiCad fork with an integrated AI agent sidebar and MCP server. Takes a complementary approach: live editor manipulation via IPC vs. our offline file-based analysis and optimization.
kipy — the official KiCad Python bindings (kicad-python on PyPI) for the KiCad IPC API. Requires a running KiCad instance with the IPC API enabled and a document open in an editor — every accessor is an RPC to the live editor; there is no offline file-reading path, so it cannot participate in headless/CI workflows. Evaluated and not adopted: see docs/research/kipy-ipc-api-evaluation.md.

License

MIT

Name		Name	Last commit message	Last commit date
.claude		.claude
.github		.github
.loom		.loom
benchmarks		benchmarks
boards		boards
data/research		data/research
docs		docs
examples		examples
notebooks		notebooks
scripts		scripts
site		site
src/kicad_tools		src/kicad_tools
tests		tests
.env.example		.env.example
.gitattributes		.gitattributes
.gitignore		.gitignore
.python-version		.python-version
AGENTS.md		AGENTS.md
CHANGELOG.md		CHANGELOG.md
CLAUDE.md		CLAUDE.md
CMakeLists.txt		CMakeLists.txt
LICENSE		LICENSE
Makefile		Makefile
README.md		README.md
RELEASING.md		RELEASING.md
ROADMAP.md		ROADMAP.md
WORK_LOG.md		WORK_LOG.md
WORK_PLAN.md		WORK_PLAN.md
loom.sh		loom.sh
package.json		package.json
pyproject.toml		pyproject.toml
uv.lock		uv.lock

Latest commit

History

Folders and files

Repository files navigation

kicad-tools

Why Agent-Focused?

Installation

Quick Start

Command Line (kct)

Python API

PCB Autorouter

LLM-Driven PCB Layout

MCP Server for AI Agents

Circuit Blocks

Project Workflow

Progress Callbacks

Parametric Footprint Generators

Symbol Library Management

Pure Python DRC

Placement Optimization

Trace Optimization

Datasheet Tools

Parts Lookup (LCSC / JLCPCB)

Using your own JLCPCB API key

CLI Commands

Unified CLI (kct or kicad-tools)

PCB Tools

Library Tools

Modules

What's New (v0.20.0, August 2026)

Features

Requirements

Development

Quick Start

Fresh worktree checklist

Available Commands

Direct uv Commands

Agent Skills (kct namespace)

Related Projects

License

About

Resources

Stars

Watchers

Forks

Releases

Packages

Used by

Contributors

Languages

Command Line (`kct`)

Unified CLI (`kct` or `kicad-tools`)

Agent Skills (`kct` namespace)