Gorfc MCP Server

gorfc-mcp-server

A Model Context Protocol (MCP) server that connects LLMs to SAP systems via RFC (Remote Function Call). It exposes SAP RFC operations as MCP tools over stdio transport, allowing AI agents to ping SAP systems, describe function modules, invoke BAPIs/RFCs, and retrieve call metrics.

Prerequisites

• Go 1.24+
• SAP NW RFC SDK installed at /usr/local/sap/nwrfcsdk/ (headers in include/, libraries in lib/)
• A SAP connection configured either via a sapnwrfc.ini file or environment variables (see Configuration)

SAP NetWeaver RFC SDK Proprietary Notice

The SAP NetWeaver RFC SDK is proprietary software owned by SAP SE. It is not open-source and is subject to specific licensing terms.

Licensing & Access

• No Redistribution: You are not permitted to redistribute the SDK binaries (.dll, .so, .dylib) in your own applications or repositories.
• Customer Access: Access requires a valid SAP license and an S-User ID for the SAP Support Portal.
• Legal Source: Binaries must only be downloaded from the official SAP Software Download Center.

Official Resources

• Product Page: SAP Support Portal - Connectors
• Master Note: SAP Note 2573790 (Installation and Availability for version 7.50).
• Technical Guide: Detailed programming guides are provided within the doc folder of the downloaded SDK package.

Build

make build           # compiles to ./gorfc-mcp-server
make build-windows   # cross-compiles to ./gorfc-mcp-server.exe (Windows x86_64)
make clean           # removes built binaries

The build uses CGO with flags pointing to the SAP NW RFC SDK:

CGO_CFLAGS="-I/usr/local/sap/nwrfcsdk/include"
CGO_LDFLAGS="-L/usr/local/sap/nwrfcsdk/lib"

Cross-compiling for Windows

The build-windows target cross-compiles for Windows x86_64 using MinGW. It requires a Windows build of the SAP NW RFC SDK with headers and libraries available at the configured SDK path and the MinGW-w64 cross-compiler (x86_64-w64-mingw32-gcc).

Install on Debian/Ubuntu:

  sudo apt install gcc-mingw-w64-x86-64

Configuration

Two connection modes are supported.

Mode 1 — ini-based (SAP_DEST)

Create a sapnwrfc.ini file (standard SAP NW RFC SDK format) in the working directory and reference the destination by name:

DEST=SID
TYPE=A
ASHOST=sap.example.com
SYSNR=00
CLIENT=100
USER=rfcuser
PASSWD=secret
LANG=EN

Note: sapnwrfc.ini contains plaintext credentials and is gitignored. Never commit this file.

Mode 2 — direct environment variables

Skip the ini file and supply connection parameters directly via environment variables.

Direct application-server connection:

Load-balancing / message-server connection:

Running

ini-based

Pass the destination name via SAP_DEST or as the first CLI argument:

SAP_DEST=SID ./gorfc-mcp-server
./gorfc-mcp-server SID

The SID is the unique, three-character alphanumeric identifier for the SAP system as defined in sapnwrfc.ini:

Direct environment variables

# Direct application-server connection
SAP_ASHOST=sap.example.com SAP_SYSNR=00 \
  SAP_CLIENT=100 SAP_USER=rfcuser SAP_PASSWD=secret \
  ./gorfc-mcp-server

# Load-balancing connection
SAP_MSHOST=msg.example.com SAP_SYSID=SID SAP_GROUP=PUBLIC \
  SAP_CLIENT=100 SAP_USER=rfcuser SAP_PASSWD=secret \
  ./gorfc-mcp-server

Logs are written to stderr with a [gorfc-mcp] prefix.

Test

# ini-based
SAP_DEST=SID go test -tags integration ./cmd/gorfc-mcp-server/

# direct env vars
SAP_ASHOST=sap.example.com SAP_SYSNR=00 SAP_CLIENT=100 \
  SAP_USER=rfcuser SAP_PASSWD=secret \
  go test -tags integration ./cmd/gorfc-mcp-server/

MCP Client Configuration

Claude Desktop

ini-based:

{
  "mcpServers": {
    "sap": {
      "command": "/path/to/gorfc-mcp-server",
      "args": ["SID"],
      "env": {
        "LD_LIBRARY_PATH": "/usr/local/sap/nwrfcsdk/lib"
      }
    }
  }
}

Direct environment variables:

{
  "mcpServers": {
    "sap": {
      "command": "/path/to/gorfc-mcp-server",
      "env": {
        "LD_LIBRARY_PATH": "/usr/local/sap/nwrfcsdk/lib",
        "SAP_ASHOST": "sap.example.com",
        "SAP_SYSNR": "00",
        "SAP_CLIENT": "100",
        "SAP_USER": "rfcuser",
        "SAP_PASSWD": "secret",
        "SAP_LANG": "EN"
      }
    }
  }
}

Claude Code

ini-based:

claude mcp add sap /path/to/gorfc-mcp-server -- SID

Direct environment variables (use claude mcp add --env flags or set them in your shell before launching):

Tools

Model Context Protocol (MCP) tools designed for SAP connectivity, metadata inspection, and table discovery via the NetWeaver RFC SDK.

Tool Overview

SAP Connectivity Tools

rfc_ping

Pings the connected SAP system to verify connectivity.

• Parameters: None.

rfc_connection_info

Returns connection attributes such as System ID, Client, Host, and the SAP NW RFC SDK version.

• Parameters: None.

rfc_describe

Returns the full metadata of an RFC function module. Use this to understand the interface before calling.

rfc_call

Invokes an RFC function module with the given parameters and returns the result.

Parameter Value Type Mapping

Data Dictionary (DDIC) Tools

get_table_metadata

SAP Function module: DDIF_FIELDINFO_GET Returns the fields of a given SAP table including field name, ABAP type, length, domain, and short description.

get_table_relations

SAP Function module: FAPI_GET_FOREIGN_KEY_RELATIONS Retrieves foreign-key relationships for the specified table, including referenced check tables and cardinalities.

search_sap_tables

SAP Function module: RFC_READ_TABLE (targeting DD02T) Performs a LIKE-style search over table short texts to find tables by description.

Additional Helper Functions

• sanitizeABAPString: Escapes single-quotes and other characters for safely embedding user strings into ABAP WHERE clauses or RFC_READ_TABLE filters.
• parseReadTableResult: Parses the legacy DATA/WA row format from RFC_READ_TABLE into a structured array of maps ([]map[string]string) keyed by column name.

Monitoring

metrics_get

Returns in-memory call statistics: total/successful/failed call counts, total and average duration, and per-function call counts.

• Parameters: None.

Architecture

All logic lives in a single file: cmd/gorfc-mcp-server/main.go.

• connManager — Thread-safe wrapper around gorfc.Connection. All RFC calls are serialized through a mutex since the SAP NW RFC SDK is not thread-safe per connection handle. Includes auto-reconnect with exponential backoff (3 retries, starting at 100ms). Constructed via newConnManager(dest) (ini-based) or newConnManagerFromParams(params) (direct parameters).
• connParamsFromEnv — Reads SAP_ASHOST/SAP_MSHOST and related env vars and returns a gorfc.ConnectionParameters map. Returns nil when no direct-connection vars are set so the caller can fall back to SAP_DEST.
• coerceParams / coerceValue — Type coercion layer that converts JSON-deserialized Go types (float64, string, etc.) to the specific Go types gorfc expects. Recursively handles structures and tables.
• validateParameters — Pre-call validation that all parameter names exist in the function description.
• metrics — In-memory call counter tracking total/success/failure counts, durations, and per-function stats.

Example Prompts

See EXAMPLES.md for example prompts to use with this server.

License

Apache License 2.0