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.

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.

The Core Idea

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

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

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.

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.

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"   │                              │               │
│    │◄────────────────────────┤                              │               │
│                                                                             │
└─────────────────────────────────────────────────────────────────────────────┘

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

Inspect & visualise

Compare

Edit in place

Manage components

Library operations

Backups & safety

Primitive Types

Footprint Primitives (PcbLib)

Pad Shapes and Pin 1 Indicator

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

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)

Standard Altium Layers

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

Additional layers supported:

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.

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.

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]

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.

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

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:

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.

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)
• 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

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.

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: matejg03@gmail.com, or a GitHub issue for anything that need not be private.

Documentation

Contributing

Contributions welcome! See CONTRIBUTING.md for guidelines.

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

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.

Licence

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

GNU General Public License v3.0 — see LICENCE.

Links

• MCP Specification
• Report an Issue

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.

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/).