altium-designer-mcp

altium-designer-mcp

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, Cursor, Antigravity, VS Code Copilot — any MCP client) 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, Cursor, Antigravity, VS Code + Copilot — any MCP client — 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

Client Setup — verified configuration for Claude Code, Claude Desktop, Google Antigravity, Cursor, VS Code, GitHub Copilot CLI, Windsurf, Cline, Roo Code, Kiro, JetBrains, Zed, Gemini CLI, Codex CLI, Continue, Goose, OpenCode and any other stdio MCP client, plus troubleshooting — on Windows, Linux, and macOS.

Using the server — what to ask for once it is connected: example workflows, prompts and tips, identical for every client.

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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 │
│    │                         ├─────────────────────────────►│               │
│    │                         │◄─────────────────────────────┤               │
│    │                         │  { status: "success" }       │               │
│    │                         │                              │               │
│    │  "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), power-plane thermal relief, and its own polygon-connect style
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), with optional hole contours
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 string (RECORD=4) — the only free text on a symbol
IeeeSymbol	IEEE symbol glyph (RECORD=3): a dot, a clock, an active-low input, …
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 1–32	User-defined mechanical layers
Drill Guide	Drill hole markers
Drill Drawing	Drill chart/table
Keep-Out Layer	Routing exclusion zones

A layer may be named as Altium spells it (Top Overlay, Mechanical 13) or in camel case (TopOverlay, Mechanical13), in any case; every tool accepts the same spellings.

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Installation

Prebuilt binaries for Linux (x86_64), macOS (aarch64) and Windows (x86_64) are on the Releases page — each archive bundles a setup README plus docs/CLIENT_SETUP.md, which wires the server into every MCP client we know of. The Linux binary needs glibc 2.34 or newer: Ubuntu 22.04, Debian 12, RHEL 9 (and its free rebuilds, AlmaLinux and Rocky Linux 9) and later.

Claude Desktop users need no archive at all: install the one-click extension altium-designer-mcp.mcpb from the same page (older builds: the identical altium-designer-mcp.dxt) via Settings → Extensions → Advanced settings → Install Extension… — see CLIENT_SETUP.md § Claude Desktop.

Code signing policy: docs/CODE_SIGNING_POLICY.md. The Windows binaries are to be signed through SignPath Foundation; until that is approved they are unsigned, and every release carries a signed build-provenance attestation.

In a container — for a Linux box, a NAS or a CI job that generates libraries into a mounted folder (Altium itself never needs to be inside): the repository’s Dockerfile produces the same --locked release build as the published binaries.

docker build -t altium-designer-mcp .
docker run -i --rm -v /path/to/libraries:/libraries altium-designer-mcp

The mounted /libraries folder is the container’s whole allow-list. In a client’s configuration that is "command": "docker" with "args": ["run", "-i", "--rm", "-v", "/path/to/libraries:/libraries", "altium-designer-mcp"].

To build from source instead, see CONTRIBUTING.md § Development Setup; an optimised binary comes from cargo build --release and lands at target/release/altium-designer-mcp.

Verifying a downloaded release

Released archives are built by GitHub Actions and carry a signed SLSA build provenance attestation, so a download can be traced back to the workflow run and commit that produced it:

gh attestation verify <archive> --repo embedded-society/altium-designer-mcp
sha256sum --check --ignore-missing SHA256SUMS.txt

The binaries are not code-signed, so Windows SmartScreen and macOS Gatekeeper warn on first run (on macOS, right-click → Open). The attestation is the stronger check. See docs/RELEASING.md for how releases are produced.

Command-Line Usage

altium-designer-mcp [OPTIONS] [CONFIG_FILE]

Option	Description
CONFIG_FILE	Path to configuration file (optional, uses default location if omitted)
--allow <DIR>...	Grant access to library folders directly (repeatable). Adds to the config file’s allowed_paths, and works with no config file at all — the other settings then take their defaults
--ansi-code-page <PAGE>	The Windows ANSI code page new footprint names are written in, tried first when a library’s page is detected, and used for a library that shows none (936 for GBK, 1250, 1252, …); overrides ansi_code_page in the config file
--http <ADDR>	Serve the MCP Streamable HTTP transport on this address (for example 127.0.0.1:8080) at the path /mcp, instead of stdio. A non-loopback address is refused unless a bearer token is set in ALTIUM_DESIGNER_MCP_HTTP_TOKEN. See docs/CLIENT_SETUP.md § HTTP transport
--http-allow-origin <ORIGIN>...	A browser origin allowed to reach the HTTP transport besides the local ones (repeatable)
-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

Connecting an AI client

Every MCP client needs the same two absolute paths — the binary and your config file — and differs only in where they are written. The standard block most clients read:

{
    "mcpServers": {
        "altium": {
            "command": "/usr/local/bin/altium-designer-mcp",
            "args": ["/home/you/.altium-designer-mcp/config.json"]
        }
    }
}

Where that goes for Claude Desktop, Cursor, VS Code, Windsurf, Cline, Zed, JetBrains, Gemini CLI, Codex CLI and the rest — and what to do when a client cannot see the server — is in docs/CLIENT_SETUP.md. Use absolute paths: clients do not search PATH or expand ~ for you.

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Configuration

The server reads one JSON file — or none: altium-designer-mcp --allow <DIR> grants folders on the command line and runs on defaults for everything else, which is how the Claude Desktop extension starts it. 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; --allow adds to it (default when neither grants anything: the current working 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)
ansi_code_page	The Windows ANSI code page new footprint names are written in: 874, 932, 936, 949, 950, 1250 to 1258 or 65001. The reader also tries it first when it detects a library’s code page, and reads a library that shows none through it. Altium Designer 21 displays a footprint’s name from those bytes through the machine’s code page, so it should be the code page of the machine whose Altium opens the libraries (default: null — the system’s code page on Windows, 1252 elsewhere)

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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 copying or merging components between libraries:

• Embedded models travel with the component — copy_component_cross_library and merge_libraries both copy the referenced model streams into the target (a model shared by several footprints is copied once), so the bodies still resolve after the move.
• External model references: copy_component_cross_library removes them with a warning by default, since a path relative to the source library rarely resolves elsewhere — pass preserve_external_paths=true to keep them. merge_libraries carries them unchanged.

Embedding a model in the source library is the reliable way to keep 3D data through any copy.

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

A backup never replaces another: a second one within the same second is MyLibrary.PcbLib.20260125_143022_001.bak, then _002, and so on.

Backup retention: The 5 most recent backups per file are kept, and so is the first one the server made of the file since it started, which holds the file as it was before the session’s changes. 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)
• restore_backup (the current file, before the chosen backup replaces it)

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

Libraries from a Non-Western Windows

Altium stores most names as plain bytes in the Windows code page of the machine that wrote them, with no record of which page that was. A library authored on a Chinese, Japanese, Korean, Central European, Cyrillic, Greek, Turkish, Baltic, Hebrew, Arabic, Vietnamese or Thai Windows therefore reads as mojibake (£¨0402 for （0402) in a tool that assumes Windows-1252.

This server works out the library’s code page from the footprints whose real name is recorded twice — once as those bytes, once in Unicode — reads every name through it, and writes it back unchanged, so a rewrite stays byte-identical. Nothing needs configuring to read or edit such a library.

Two cases are worth knowing:

• A name your Altium must display. Altium Designer 21 and earlier show a footprint’s name from those bytes, decoded through the code page of the machine they run on, and never read the Unicode copy. A new or renamed footprint is therefore written in the server’s own code page — the system’s on Windows. When the server runs on a machine with a different locale from the Altium that opens the libraries, name that page with ansi_code_page in the configuration file or --ansi-code-page on the command line (874, 932, 936, 949, 950, 1250 to 1258, or 65001).
• A character the page cannot hold. Altium writes ? in its place, and so does this server; the full name is still preserved in the component parameters, as Altium preserves it, and comes back intact on the next read.

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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Privacy Policy

altium-designer-mcp is a local tool and collects nothing.

• Data collection: none. The server has no telemetry and no analytics, and it never contacts any service, including this project’s. With --http it listens for an MCP client on the address you give; it still sends nothing anywhere.
• Usage and storage: it reads and writes only the library files inside the folders you grant (allowed_paths or --allow), plus the timestamped .bak copies it makes beside them before a change. The optional audit log (logging.audit_log_path) is a local file you choose, holding tool names, file names and outcomes — never library contents.
• Third-party sharing: none. Nothing leaves your machine.
• Data retention: the files and backups stay until you delete them; backups are capped at the five most recent per library.
• Contact: [email protected], or a GitHub issue for anything that need not be private.

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Documentation

For…	Read
Wiring the server into your AI client	docs/CLIENT_SETUP.md — one section per client
What to ask for once it is connected	docs/USAGE.md — workflows, prompts, tips
Telling the AI how to use it well	docs/AGENT_GUIDE.md (paste into a project brief), docs/AI_WORKFLOW.md
Every tool, parameter and example	docs/TOOLS.md; error messages in docs/errors.md
Why it is built this way	docs/VISION.md, docs/ARCHITECTURE.md
The file formats, byte by byte	docs/PCBLIB_FORMAT.md, docs/SCHLIB_FORMAT.md
Security model and threat analysis	docs/SECURITY.md (reporting: SECURITY.md)
How releases are built and verified	docs/RELEASING.md; code signing policy

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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

Write-path tests generate their own data programmatically; reader tests parse the committed Altium-authored golden fixtures (see Sample Files). 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 © 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/).