arc1-adt-abap-mcp-ext

arc1-adt-abap-mcp-ext

Use Claude, GitHub Copilot, Cursor, or any MCP-capable AI client to read your ABAP system — without leaving Eclipse.

Drop one JAR into your Eclipse dropins/, turn on SAP's built-in MCP server, restart, point your AI client at http://localhost:2234/mcp — done. Your AI can now search ABAP repositories, read source code, list transports, inspect service bindings, and more.

Important

Requires ABAP Development Tools (ADT) 3.60 or newer. Version 0.5.1 builds on SAP's supported MCP server, which first shipped an activation surface in ADT 3.60. For ADT 3.58 / 3.59 use plugin version ≤ 0.3.x instead (those reflectively woke the then-dormant server).

What this actually does

As of ADT 3.60, SAP ships a supported MCP server inside Eclipse-for-ABAP. It's off by default and, on its own, only exposes SAP's own MCP tools. This plugin:

1. Adds 18 read-only ABAP tools via SAP's documented Eclipse extension point com.sap.adt.mcp.core.adtMcpTools — search, read source, object metadata, where-used, package/object structure, syntax check, unit tests, ATC, transports, and authenticated HTTP escape hatches.
2. Logs you in automatically to your ABAP project (optional) so the AI can reach the backend on the first call.

You enable SAP's server once (a preference toggle + one eclipse.ini line); this plugin's tools then register on it automatically every time it starts. No reflection, no internal hacks — just a standard tool contribution.

Note

This is a community plugin, not an official SAP product. It uses only the documented extension point. SAP owns the server lifecycle (start/stop, port, token); this plugin only contributes tools.

Quick install (5 minutes)

What you need first

• Eclipse for ABAP with ADT 3.60+ (check via Help → Installation Details)
• JDK 21 — comes bundled with Eclipse-for-ABAP, no separate install needed
• An ABAP project that you can log into (this plugin connects through it)

Step 1: Download the plugin JAR

From the latest release, grab com.arc1.mcp_0.5.1.jar.

Step 2: Drop it into Eclipse's dropins/ folder

If your Eclipse is somewhere else, look for the dropins/ folder next to your Eclipse executable (or one level up on macOS — inside the .app).

Step 3: Add one line to eclipse.ini

Find eclipse.ini (next to the Eclipse executable, or inside the macOS app bundle at Contents/Eclipse/eclipse.ini). Add this line at the very bottom, after the existing -vmargs block:

-DadtMcpServerPrefEnabled=true

This is SAP's flag that makes the MCP server auto-start on every boot. Without it, the server only runs while you keep the preference applied in the current session.

(Optional) if you want this plugin to auto-log-into a specific ABAP project, also add:

-Darc1.mcp.destination=YOUR_DESTINATION_ID

See how to find your destination ID below.

Step 4: Restart Eclipse with -clean

# macOS
pkill -f Eclipse
~/eclipse/java-2025-09/Eclipse.app/Contents/MacOS/eclipse -clean &

# Linux
pkill -f eclipse
~/eclipse/java-2025-09/eclipse/eclipse -clean &

Windows: close Eclipse normally, then run eclipse.exe -clean from a command prompt. The -clean flag is only needed once per plugin update.

Step 5: Turn on the MCP server (SAP preference page)

In Eclipse: Preferences → ABAP Development → MCP Server.

1. Tick Enable ADT MCP Server.
2. Leave Token blank and click Generate (or type your own long string).
3. Port defaults to 2234 — change it only if that port is taken.
4. Click Apply. You should see "ADT MCP Server started successfully."

Copy the Token value — you'll paste it into your AI client in the next section. (SAP shows it right there on the page; this plugin does not write a token file.)

Step 6: Verify it started

Window → Show View → Error Log. You should see (from SAP and from us):

ADT MCP Server started successfully.
ARC-1 MCP extension: tool contributions registered. The ADT MCP server is started by SAP ...
ARC-1 MCP extension: Auto-login succeeded for destination: YOUR_DESTINATION_ID

If you see those, you're done with the plugin install. Now connect a client.

Connect your AI client

Use the port and token from the preference page (default port 2234). Pick one client below:

{
  "servers": {
    "mcp-abap-server": {
      "url": "http://localhost:2234/mcp",
      "requestInit": {
        "headers": {
          "Authorization": "Bearer PASTE-TOKEN-FROM-PREFERENCE-PAGE"
        }
      }
    }
  }
}

claude mcp add abap http://localhost:2234/mcp \
  --header "Authorization: Bearer PASTE-TOKEN-FROM-PREFERENCE-PAGE" \
  --transport http

{
  "mcpServers": {
    "abap": {
      "command": "npx",
      "args": [
        "mcp-remote", "http://localhost:2234/mcp",
        "--header", "Authorization: Bearer PASTE-TOKEN-FROM-PREFERENCE-PAGE"
      ]
    }
  }
}

How to find your destination ID

The destination ID is the internal name of your ABAP project's connection. It's not the SID; it looks like A4H_001_marian_en_1 (<SID>_<client>_<user>_<lang>_<seq>).

Easiest: open ADT's Project Explorer. The name shown for your ABAP project is the destination ID. Copy it.

Other ways:

• Right-click ABAP project → Properties → ABAP Project
• Once the server is running, call abap_list_destinations (SAP's built-in tool) from your AI client and read the IDs back

If you skip -Darc1.mcp.destination=... entirely, the plugin auto-picks the first available ABAP project. Set it explicitly when you have multiple projects.

Troubleshooting

The MCP server never starts

• Make sure you ticked Enable ADT MCP Server under Preferences → ABAP Development → MCP Server and clicked Apply.
• For auto-start on boot, confirm -DadtMcpServerPrefEnabled=true is in eclipse.ini (under -vmargs) and you restarted. Without that flag, the server does not come back after an Eclipse restart.
• Port already taken by another process: change the port on the preference page (e.g. 2235) and update the URL in your AI client config.

arc1_sap_* tools don't show up in tools/list (only SAP's tools do)

The plugin bundle didn't load. Check Help → About Eclipse → Installation Details → Plug-ins for com.arc1.mcp. If it's missing:

• Confirm the JAR is in dropins/ (not a subfolder), then restart with -clean.
• Confirm your ADT version is 3.60+ — this plugin refuses to load on older ADT (the OSGi requirement is [3.60.0,4.0.0)).

Tool calls return HTTP 401

The token your AI client sent doesn't match the one on the preference page. Open Preferences → ABAP Development → MCP Server, copy the Token value, and update the Authorization: Bearer ... header in your client config. Restart your AI client after changing its config. If the header is missing entirely, your client isn't sending Authorization at all — it must be named exactly Authorization with a value starting Bearer (with a space).

arc1_sap_search returns "Unable to initialize the ADT Discovery"

You're not logged into the ABAP project yet. In Project Explorer, expand your ABAP project — Eclipse will prompt for the password. Tick "Save password" so future restarts log in silently. (Or set -Darc1.mcp.destination=... so this plugin pre-logs-in for you.)

What you get — the tools

Plugin tools (18, all read-only)

Search + metadata (v0.1.0)

Source reading + HTTP (v0.2.0)

Transports + POST (v0.3.0)

Navigation + structure + quality (v0.5.0)

SAP's own MCP tools (alongside these)

When the server is running, SAP also contributes its own tools (the exact set depends on which ADT features are installed). On a typical S/4 ADT install that includes:

abap_list_destinations, abap_generators-list_generators, abap_generators-get_schema, abap_generators-generate_objects, abap_transport-get, abap_transport-create, abap_business_services-fetch_services, abap_business_services-fetch_service_information.

These are SAP's, not this plugin's — they ship and register on their own.

Verify everything works (full smoke test)

If you have the source checked out, pass the server URL + token from the preference page via environment variables:

git clone https://github.com/marianfoo/arc1-adt-abap-mcp-ext.git
cd arc1-adt-abap-mcp-ext

export ARC1_MCP_URL=http://localhost:2234/mcp     # port from the preference page
export ARC1_MCP_TOKEN=PASTE-TOKEN-FROM-PREFERENCE-PAGE
./scripts/smoke-test.sh A4H_001_marian_en_1       # use your destination ID

This exercises all 18 plugin tools through the MCP protocol end-to-end and prints the responses.

Configuration reference

The MCP server's port, token, and on/off live in SAP's preference page (Preferences → ABAP Development → MCP Server) and the eclipse.ini flag -DadtMcpServerPrefEnabled=true. This plugin adds only two optional knobs, set via JVM -D flags in eclipse.ini:

Build from source

git clone https://github.com/marianfoo/arc1-adt-abap-mcp-ext.git
cd arc1-adt-abap-mcp-ext
./build.sh                # produces com.arc1.mcp_<version>.jar
INSTALL=yes ./build.sh    # also copies to your local Eclipse dropins/

No Maven, no Tycho. build.sh uses the JDK and SAP ADT JARs (3.60+) from your local Eclipse install (~/.p2/pool/plugins/). Build time: ~3 seconds.

How it works (deep dive)

• Architecture overview: docs/architecture.md
• Why each design decision: docs/decisions.md
• Underlying research (SAP bytecode analysis, ADT API maps): docs/research/
• Implementation plans (one per release): docs/plans/

TL;DR: SAP designed the MCP server to be extended via the standard Eclipse extension point com.sap.adt.mcp.core.adtMcpTools. This plugin contributes 18 <mcpTool class="..."/> entries, which SAP's own ToolRegistrationService picks up whenever the server starts. SAP owns activation (the preference page

• -DadtMcpServerPrefEnabled=true); this plugin never touches the server lifecycle.

FAQ

Is this an official SAP product?

No. It's a community plugin. See the note at the top.

Why do I need ADT 3.60?

ADT 3.60 is the first release where SAP shipped a way to turn the MCP server on (a preference page + startup flag) and a stable startMCPServer signature. Earlier releases (3.58/3.59) had the server but no activation surface — plugin versions ≤ 0.3.x handled those by reflectively waking it. 0.4.0 drops that and relies on SAP's supported activation, so it's 3.60+ only.

Does this read or modify my source code?

The 18 tools this plugin adds are read-only with respect to your repository — none create, change, or delete source. Two execute code on the backend without changing it: arc1_sap_run_unit_tests runs an object's ABAP Unit tests and arc1_sap_atc_check runs ATC static analysis (the same as the corresponding ADT menu actions). arc1_sap_check_syntax can validate proposed source transiently without saving it. SAP's own MCP tools may include genuinely mutating workflows (abap_generators-generate_objects, abap_transport-create). All of these use your normal SAP authorizations — same as the equivalent ADT UI action.

What about credentials / security?

• The MCP server binds to localhost only (not reachable from the network).
• Every request requires the bearer token set on SAP's preference page.
• SAP backend calls use your existing ABAP-project authentication (cookies / SSO / saved password).
• No telemetry, no outbound HTTP from this plugin.

How do I add my own tool?

Implement com.sap.adt.mcp.core.IAdtMCPTool in your own bundle and contribute via plugin.xml. See CONTRIBUTING.md for the recipe.

What's the relationship to ARC-1?

ARC-1 is the standalone TypeScript MCP server for SAP ABAP — runs outside Eclipse, has admin policy ceiling, audit logging, multi-client governance, BTP-native deployment. Use ARC-1 when you want a centralized managed service. Use this plugin when you want "one developer, inside Eclipse, zero extra processes".

What about adt-ls? Can this plugin use it?

adt-ls is a TypeScript/Node SDK that spawns and drives SAP's headless adt-ls language server over LSP + MCP. It's the out-of-Eclipse cousin of this plugin: a programmatic API for repository, source, activate, unit tests, ATC, syntax check, and transports — great for scripting and CI.

This plugin does not depend on it, by design. We already run inside Eclipse-for-ABAP, which is the full ADT — pulling in adt-ls would spawn a second, headless ADT (Java → Node → another JVM) to reach a backend we already reach in-process, and would add a third-party runtime plus an extra process (both ruled out — see decision D10).

Pick by where you run:

Where do I report bugs?

GitHub Issues. Include your Eclipse + ADT versions, plugin version (the JAR filename), and the relevant excerpt from the Error Log (filter by com.arc1.mcp).

License

MIT — use it, modify it, ship it.