Altium Designer

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Let an AI build your Altium libraries — it does the engineering, this tool writes the files.

An MCP server that gives AI assistants (Claude Code, Claude Desktop, Google Antigravity, VSCode Copilot) file I/O and primitive-placement tools for Altium Designer .PcbLib (footprint) and .SchLib (symbol) libraries — so the AI can create and maintain any component, not just pre-programmed packages.

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The Problem

Building Altium component libraries by hand is slow and repetitive — every footprint means looking up IPC-7351B pad sizes, courtyards, and silkscreen, then placing each primitive by hand. AI assistants are excellent at exactly that reasoning, but they cannot write Altium's binary .PcbLib/.SchLib files — an undocumented OLE compound format that is easy to corrupt, and Altium silently refuses to open a malformed file.

Approach	Problem
Draw every footprint by hand in Altium	Slow and repetitive; the AI can't touch the file
Ask an AI to emit the binary file directly	It produces a corrupt file Altium won't open
Pre-programmed footprint generators	Only the package types someone coded in advance

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The Core Idea

The AI handles the intelligence. The tool handles file I/O.

Responsibility	Owner
IPC-7351B calculations	AI
Package layout decisions	AI
Style choices	AI
Datasheet interpretation	AI
Reading/writing Altium files	This tool
Primitive placement	This tool
STEP model attachment	This tool

This means the AI can create any footprint — not just pre-programmed package types. See docs/VISION.md for the full architectural rationale.

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Who Is This For?

Anyone who builds or maintains Altium component libraries and uses an MCP-capable AI assistant. The AI does the engineering (datasheet → dimensions → style); this server lets it read and write the actual .PcbLib / .SchLib files.

If you…	Then…
Use Claude Code, Claude Desktop, or VSCode + Copilot and design in Altium	✅ This is for you
Want pre-baked generators for a fixed set of packages	❌ Not this — the point is any component
Don't use Altium	❌ Not applicable

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Quick Start with Claude Code

Claude Code Setup Guide — Complete step-by-step instructions for using this MCP server with Claude Code CLI on Windows, Linux, and macOS.

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Quick Start with Google Antigravity

Google Antigravity Setup Guide — Step-by-step instructions for using this MCP server with Google Antigravity (IDE and CLI) on Windows, Linux, and macOS.

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How It Works

┌─────────────────────────────────────────────────────────────────────────────┐
│  AI-ASSISTED COMPONENT CREATION                                             │
│                                                                             │
│  Engineer                    AI                         MCP Server          │
│    │                         │                              │               │
│    │  "Create 0603 resistor" │                              │               │
│    ├────────────────────────►│                              │               │
│    │                         │                              │               │
│    │                         │  AI reasons about:           │               │
│    │                         │  • IPC-7351B pad sizes       │               │
│    │                         │  • Courtyard margins         │               │
│    │                         │  • Silkscreen/symbol style   │               │
│    │                         │                              │               │
│    │                         │  write_pcblib(primitives)    │               │
│    │                         ├─────────────────────────────►│               │
│    │                         │                              │ Writes        │
│    │                         │                              │ .PcbLib +     │
│    │                         │  write_schlib(symbol)        │ .SchLib files │
│    │                         ├─────────────────────────────►│               │
│    │                         │◄─────────────────────────────┤               │
│    │                         │  { success: true }           │               │
│    │                         │                              │               │
│    │  "Done! Footprint       │                              │               │
│    │   and symbol created"   │                              │               │
│    │◄────────────────────────┤                              │               │
│                                                                             │
└─────────────────────────────────────────────────────────────────────────────┘

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MCP Tools

The server exposes 34 tools, working on both .PcbLib (footprints) and .SchLib (symbols). Every tool's full parameters and examples live in docs/TOOLS.md — this is the categorised overview.

Read & write

Tool	Purpose
read_pcblib	Read footprints from a .PcbLib.
write_pcblib	Write footprints to a .PcbLib.
read_schlib	Read symbols from a .SchLib.
write_schlib	Write symbols to a .SchLib.

Inspect & visualise

Tool	Purpose
list_components	List component names (paginated).
get_component	Get one component's full data.
search_components	Search across libraries by regex/glob.
component_exists	Check whether components exist.
render_footprint	ASCII-art preview of a footprint.
render_symbol	ASCII-art preview of a symbol.
extract_style	Extract styling from an existing library.

Compare

Tool	Purpose
diff_libraries	Compare two library files.
compare_components	Diff two specific components.

Edit in place

Tool	Purpose
update_component	Update a component, preserving its position.
update_pad	Update one pad's properties.
update_primitive	Update one primitive (track/arc/text/fill/region).
batch_update	Batch updates across all components.
reorder_components	Reorder components in a library.
manage_schlib_parameters	List/get/set/remove SchLib parameters.
manage_schlib_footprints	Manage footprint links in SchLib symbols.

Manage components

Tool	Purpose
delete_component	Delete one or more components.
copy_component	Duplicate a component within a library.
rename_component	Rename a component (atomic).
copy_component_cross_library	Copy a component to another library.
bulk_rename	Pattern-based multi-rename.

Library operations

Tool	Purpose
merge_libraries	Merge multiple libraries into one.
write_libpkg	Write a .LibPkg project grouping libraries for IntLib compilation.
export_library	Export to JSON/CSV.
import_library	Import from JSON (inverse of export).
validate_library	Validate for common issues.
repair_library	Remove orphaned data.
extract_step_model	Extract embedded STEP 3D models.

Backups & safety

Tool	Purpose
list_backups	List automatic backups.
restore_backup	Restore from a backup.

Primitive Types

Footprint Primitives (PcbLib)

Primitive	Description
Pad	SMD or through-hole pad with designator, position, size, shape, layer (see Pad Shapes below)
Via	Vertical interconnect with layer span, hole size, and thermal relief
Track	Line segment on any layer (silkscreen, assembly, etc.)
Arc	Arc or circle on any layer
Region	Filled polygon (courtyard, copper pour)
Text	Text string with font, size, position, layer
Fill	Filled rectangle on any layer
ComponentBody	3D model reference (embedded STEP models)

Pad Shapes and Pin 1 Indicator

The shape property on pads controls the copper shape. Use this to indicate pin 1:

Shape	Value	Usage
Rectangle	"rectangle"	Pin 1 indicator — use for the first pad to distinguish it visually
Rounded Rectangle	"rounded_rectangle"	Default for SMD pads (most common)
Round	"round" or "circle"	Circular pads, default for through-hole (both values are equivalent)
Oval	"oval"	Oblong pads for constrained spaces
Octagonal	"octagonal"	Eight-sided pads (chamfered corners)

Example — marking pin 1 with a rectangular pad:

{
    "pads": [
        { "designator": "1", "x": -0.75, "y": 0, "width": 0.9, "height": 0.95, "shape": "rectangle" },
        { "designator": "2", "x": 0.75, "y": 0, "width": 0.9, "height": 0.95, "shape": "rounded_rectangle" }
    ]
}

This follows the IPC-7351 convention where pin 1 has a distinct shape (typically rectangular or square corners) while other pads use rounded corners.

Symbol Primitives (SchLib)

Primitive	Description
Pin	Component pin with name, designator, electrical type, orientation
Rectangle	Filled or unfilled rectangle (component body)
RoundRect	Rounded rectangle with corner radii
Line	Single line segment
Polyline	Multiple connected line segments
Polygon	Filled polygon with border and fill colours
Arc	Arc or circle
Pie	Filled circular sector (arc geometry plus fill)
Image	Embedded or linked raster picture with a bounding box
Ellipse	Ellipse or circle (filled or unfilled)
EllipticalArc	Elliptical arc segment with fractional radii
Bezier	Cubic Bezier curve (4 control points)
Label	Text label (RECORD=4)
Text	Text annotation (RECORD=3)
TextFrame	Bordered multi-line text box (word-wrap, alignment)
Parameter	Component parameter (Value, Part Number, etc.)
FootprintModel	Reference to a footprint in a PcbLib

Standard Altium Layers

Common layers for footprints (each has a Bottom equivalent):

Layer	Usage
Top Layer	Copper pads (SMD)
Bottom Layer	Bottom copper pads
Multi-Layer	Through-hole pads (all copper layers)
Top Overlay	Silkscreen
Top Paste	Solder paste stencil
Top Solder	Solder mask openings
Top Assembly	Assembly outline (documentation)
Top Courtyard	Courtyard boundary (IPC-7351)
Top 3D Body	3D model outline

Additional layers supported:

Layer	Usage
Mid-Layer 1–30	Internal copper layers
Internal Plane 1–16	Power/ground planes
Mechanical 1–16	User-defined mechanical layers
Drill Guide	Drill hole markers
Drill Drawing	Drill chart/table
Keep-Out Layer	Routing exclusion zones

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Installation

See CONTRIBUTING.md § Development Setup for build instructions.

The release binary will be at target/release/altium-designer-mcp.

Command-Line Usage

altium-designer-mcp [OPTIONS] [CONFIG_FILE]

Option	Description
CONFIG_FILE	Path to configuration file (optional, uses default location if omitted)
-v, --verbose	Increase logging verbosity (-v info, -vv debug, -vvv trace)
-q, --quiet	Decrease logging verbosity (only show errors)
-h, --help	Print help information
-V, --version	Print version information

Usage with Claude Desktop

Add to your Claude Desktop MCP configuration:

{
    "mcpServers": {
        "altium": {
            "command": "altium-designer-mcp",
            "args": ["/path/to/config.json"]
        }
    }
}

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Configuration

Configuration file location:

• Linux/macOS: ~/.altium-designer-mcp/config.json
• Windows: %USERPROFILE%\.altium-designer-mcp\config.json

{
    "allowed_paths": [
        "/path/to/your/altium/libraries",
        "/another/library/path"
    ],
    "logging": {
        "level": "warn"
    }
}

Configuration Options

Option	Description
allowed_paths	Array of directory paths where library files can be accessed (default: current directory)
logging.level	Log level: trace, debug, info, warn, error (default: warn)
logging.audit_log_path	Path to an append-only JSON-lines audit log of destructive operations (default: null — no audit log is written)
rate_limit.max_burst	Maximum burst of mutating operations before throttling; read-only tools are never rate limited (default: 120)
rate_limit.refill_per_sec	Token-bucket refill rate for mutating operations, in tokens per second (default: 30.0)

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STEP Model Integration

STEP models are attached, not generated. The tool links existing STEP files to footprints.

{
    "step_model": {
        "filepath": "./3d-models/0603.step",
        "x_offset": 0,
        "y_offset": 0,
        "z_offset": 0,
        "rotation": 0
    }
}

Embedded vs External Models

Altium supports two ways to reference 3D models:

Type	Storage	Portability
Embedded	STEP data stored inside the .PcbLib file	Fully portable — the model travels with the library
External	File path reference to a .step file on disk	Not portable — requires the file to exist at the referenced path

When using copy_component_cross_library or merge_libraries:

• Embedded models are copied along with the component
• External model references are removed with a warning, as the file paths are not portable across different machines or directory structures

To preserve 3D models when copying components, ensure they are embedded in the source library (not external references).

Extracting Embedded Models

Use extract_step_model to extract embedded STEP data from a library:

{
    "name": "extract_step_model",
    "arguments": {
        "filepath": "./MyLibrary.PcbLib",
        "output_path": "./extracted_model.step"
    }
}

For parametric 3D model generation, a dedicated mechanical MCP server is planned as a future project.

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Automatic Backups

Before any destructive operation (delete, update, merge, batch update), the server automatically creates a timestamped backup of the target file. Backups use the format:

MyLibrary.PcbLib.20260125_143022.bak

Backup retention: Only the 5 most recent backups per file are kept. Older backups are automatically removed to prevent unbounded disk usage.

Operations that create backups:

• delete_component
• update_component
• update_pad
• update_primitive
• rename_component
• copy_component
• copy_component_cross_library (target file)
• merge_libraries (target file)
• reorder_components
• batch_update
• bulk_rename
• repair_library
• manage_schlib_parameters
• manage_schlib_footprints
• write_pcblib / write_schlib (when overwriting)
• import_library (when overwriting)

Managing backups: Use list_backups to view available backups and restore_backup to recover from a previous version.

Dry-run support: These operations support dry_run=true to preview changes without modifying files:

• delete_component — preview which components would be deleted
• update_component — preview component replacement changes
• update_pad / update_primitive — preview property changes
• bulk_rename — preview name changes
• repair_library — preview orphaned references to remove
• batch_update — preview library-wide updates
• copy_component / rename_component / merge_libraries

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Notes

Long Component Names

Component names longer than 31 characters are supported. The OLE Compound File format limits storage names to 31 characters, so longer names are automatically truncated internally while the full name is preserved in component parameters. This is handled transparently — you can use any length component name and it will be preserved on read/write roundtrips.

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Contributing

Contributions welcome! See CONTRIBUTING.md for guidelines.

• Follow the style guide in STYLE.md
• Security issues: see SECURITY.md

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Development

cargo test

Tests are self-contained and generate their own data programmatically. Temporary files are created in .tmp/ (git-ignored) and automatically cleaned up.

The full build, formatting, and lint commands are canonical in CONTRIBUTING.md § Development Setup.

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Licence

Copyright (C) 2026 The Embedded Society https://github.com/embedded-society/altium-designer-mcp.

GNU General Public License v3.0 — see LICENCE.

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Links

• MCP Specification
• Report an Issue

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Sample Files

Altium-authored sample libraries are committed under scripts/samples/ as golden fixtures: the reader tests (tests/samples_pcblib.rs, tests/samples_schlib.rs) parse them in CI as ground truth. The PowerShell/DelphiScript tooling that (re)generates them needs a real Altium installation and is manual-only.

See scripts/README.md for details on the sample files and the on-site tooling.

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Prior Art & Acknowledgements

This project stands on the shoulders of several excellent open-source efforts, and we're grateful for each:

• AltiumSharp (MIT) — the most complete open Altium reader/writer. Used as the authoritative reference (its DTOs, binary serialisation code, and golden TestData) for verifying our binary format against ground truth.
• pyAltiumLib — an independent Python reader, used as our CI readability oracle (tests/integration/) to check that generated files actually parse.
• python-altium — early Altium format documentation.
• coffeenmusic/altium-mcp (MIT) — an MCP server that drives the live Altium application. It's the complement to this project (we generate and edit library files offline; it controls a running session). We adapted its RunScript launch + file-based bridge pattern for our on-site Altium automation (scripts/altium/).