arc1 — SAP ADT MCP Server

ARC-1 (ABAP Relay Connector) — Enterprise-ready proxy between AI clients and SAP systems.

arc1 is a TypeScript MCP server (distributed as an npm package and Docker image) that implements the Model Context Protocol (MCP) and translates AI tool calls into SAP ABAP Development Tools (ADT) REST API requests. It works with Claude, GitHub Copilot, VS Code, and any MCP-compatible client.

This repository (marianfoo/arc-1) is the actively maintained fork, continued from the original oisee/vibing-steampunk.

Why arc1?

| | abap-adt-api | mcp-abap-adt | arc1 | |---|:---:|:---:|:---:| | npm package + Docker image | — | — | Y | | Read-only mode / package whitelist | — | — | Y | | Transport controls (CTS safety) | — | — | Y | | HTTP Streamable transport (Copilot Studio) | — | — | Y | | 11 intent-based tools (~5K schema tokens) | — | — | Y | | Method-level read/edit (95% token reduction) | — | — | Y | | Context compression (7–30x) | — | — | Y | | Works with 8+ MCP clients | — | — | Y |

As an admin, you control what the AI can and cannot do:

• Restrict to read-only, specific packages, or whitelisted operations
• Require transport assignments before any write
• Block free-form SQL execution
• Allow or deny individual operation types per deployment

Quick Start

# Run directly with npx (no install needed)
npx arc-1 --url https://your-sap-host:44300 --user YOUR_USER

# Or install globally
npm install -g arc-1
arc1 --url https://your-sap-host:44300 --user YOUR_USER

# Or use Docker
docker run -e SAP_URL=https://host:44300 -e SAP_USER=dev -e SAP_PASSWORD=secret \
  ghcr.io/marianfoo/arc-1

Connect Your Client

Claude Desktop

Add to ~/.config/claude/claude_desktop_config.json:

{
  "mcpServers": {
    "sap": {
      "command": "npx",
      "args": ["-y", "arc-1"],
      "env": {
        "SAP_URL": "https://your-sap-host:44300",
        "SAP_USER": "your-username",
        "SAP_PASSWORD": "your-password"
      }
    }
  }
}

Claude Code

Add .mcp.json to your project root:

{
  "mcpServers": {
    "sap": {
      "command": "npx",
      "args": ["-y", "arc-1"],
      "env": {
        "SAP_URL": "https://your-sap-host:44300",
        "SAP_USER": "your-username",
        "SAP_PASSWORD": "your-password"
      }
    }
  }
}

GitHub Copilot / VS Code (HTTP Streamable)

Start arc1 as an HTTP server, then point your MCP client to it:

SAP_URL=https://host:44300 SAP_USER=dev SAP_PASSWORD=secret \
  npx arc-1 --transport http-streamable --port 3000

Add to VS Code / Copilot MCP config:

{
  "mcpServers": {
    "sap": {
      "url": "http://localhost:3000/mcp"
    }
  }
}

HTTP Streamable is also the transport for Copilot Studio (Microsoft Power Platform integrations).

Other MCP Clients (Gemini CLI, OpenCode, Goose, Qwen, …)

All MCP clients that support stdio work out of the box — just point them at npx arc-1.

Tools

arc1 exposes 11 intent-based tools (~5K schema tokens):

| Tool | What it does | |------|-------------| | SAPRead | Read ABAP source, table data, CDS views, message classes, class info | | SAPSearch | Find objects by name with wildcards | | SAPWrite | Create/update ABAP source code with auto lock/unlock | | SAPActivate | Activate (publish) ABAP objects | | SAPNavigate | Go-to-definition, find references, code completion | | SAPQuery | Execute ABAP SQL queries against SAP tables | | SAPTransport | CTS transport management (list, create, release) | | SAPContext | Compressed dependency context for LLM efficiency | | SAPLint | ABAP lint and code quality checks | | SAPDiagnose | Runtime errors (short dumps), profiler traces, SQL traces | | SAPManage | System feature probing and status |

Full tool reference: docs/tools.md

Token Efficiency

Method-level surgery — read or edit a single method, not the whole class:

SAPRead(type="CLAS", name="ZCL_CALCULATOR", include="implementations")
SAPWrite(action="update", type="CLAS", name="ZCL_CALCULATOR", source="...")

Up to 20x fewer tokens vs full-class round-trips.

Context compression — SAPContext auto-appends public API signatures of all referenced classes and interfaces (7–30x compression). One call = source + full dependency context.

Admin Controls (Safety)

Configure what the AI is allowed to do before deployment:

# Read-only mode — no writes at all
arc1 --read-only

# Restrict to specific packages (wildcards supported)
arc1 --allowed-packages "ZPROD*,$TMP"

# Block free-form SQL
arc1 --block-free-sql

# Whitelist operation types (R=Read, S=Search, Q=Query, …)
arc1 --allowed-ops "RSQ"

Full safety reference:

| Flag / Env | Default | Effect | |---|:---:|---| | --read-only / SAP_READ_ONLY | false | Block all write operations | | --block-free-sql / SAP_BLOCK_FREE_SQL | false | Block RunQuery execution | | --allowed-ops / SAP_ALLOWED_OPS | (all) | Whitelist operation types | | --disallowed-ops / SAP_DISALLOWED_OPS | (none) | Blacklist operation types | | --allowed-packages / SAP_ALLOWED_PACKAGES | (all) | Restrict to packages (wildcards: Z*,$TMP) |

Configuration

Priority order: CLI flags > environment variables > .env file > defaults.

# Basic
arc1 --url https://host:44300 --user admin --password secret

# Cookie auth (SSO / Fiori Launchpad)
arc1 --url https://host:44300 --cookie-file cookies.txt

Full configuration reference: CLAUDE.md

Documentation

| Doc | Description | |-----|-------------| | docs/setup-guide.md | Start here — deployment options, auth methods, decision tree | | docs/architecture.md | System architecture with Mermaid diagrams | | docs/tools.md | Complete tool reference (11 intent-based tools) | | docs/mcp-usage.md | AI agent usage guide & workflow patterns | | docs/docker.md | Full Docker reference | | docs/enterprise-auth.md | Enterprise authentication (all methods) | | docs/sap-trial-setup.md | SAP BTP trial setup | | docs/roadmap.md | Planned features | | CLAUDE.md | AI development guidelines (codebase structure, patterns) |

Development

npm ci                    # install dependencies
npm run build             # TypeScript → dist/
npm test                  # unit tests (no SAP system required)
npm run test:integration  # integration tests (skipped if no SAP vars set)

See CLAUDE.md for codebase structure and contribution guidelines.

Releasing

Releases are fully automated via release-please and GitHub Actions.

How it works

1. Merge PRs to main using Conventional Commits:

   • feat: add SAPDeploy tool → minor bump (0.1.0 → 0.2.0)
   • fix: handle empty XML response → patch bump (0.1.0 → 0.1.1)
   • feat!: rename tools or BREAKING CHANGE: in body → major bump (0.1.0 → 1.0.0)
   • chore:, docs:, ci: → no release

2. release-please automatically creates a Release PR that accumulates all changes since the last release, with a bumped version and generated CHANGELOG.md.

3. Merge the Release PR when you're ready. This triggers:

   • npm publish with provenance (trusted publishing via OIDC, no tokens)
   • Docker push to ghcr.io/marianfoo/arc-1 with semver tags (:0.2.0, :0.2, :latest)
   • GitHub Release with auto-generated release notes

Versioned artifacts

| Artifact | Location | |----------|----------| | npm package | npmjs.com/package/arc-1 | | Docker image | ghcr.io/marianfoo/arc-1:{version} | | GitHub Release | Releases |

CI workflows

| Workflow | Trigger | Purpose | |----------|---------|---------| | test.yml | push / PR to main | Lint, typecheck, unit tests (Node 20/22/24) | | release.yml | push to main | release-please PR; on merge: npm + Docker + GitHub Release | | docker.yml | push to main | Dev latest Docker image (every commit) |

Credits

| Project | Author | Contribution | |---------|--------|--------------| | abap-adt-api | Marcello Urbani | TypeScript ADT library, definitive API reference | | mcp-abap-adt | Mario Andreschak | First MCP server for ABAP ADT | | abaplint | Lars Hvam | ABAP parser/linter (used via @abaplint/core) |

License

MIT