BAUER GROUP - BG-MCPCore

BAUER GROUP MCP framework — config-driven, pluggable REST-API MCP servers on FastMCP.

bg-mcpcore is the shared foundation for BAUER GROUP's fleet of Model Context Protocol servers that bridge REST APIs (Zammad, Shlink, and more). It turns "stand up a secure, OAuth-gated MCP server for an API" from a multi-day clone-and-edit job into a short declarative profile.

Repository Information:

• Version: v1.6.0 (2026-06-02)
• Repository: bauer-group/LIB-BG-MCPCore
• Branch: main
• Architecture: Config-driven, pluggable, secure-by-default

The idea: config for the standard, code for the complex

A server is described by a declarative JSON profile. Standard behaviour — identity, backend connection, inbound/outbound auth, rate limiting, observability, health/branding routes, and OpenAPI-derived tools — needs no Python. The genuinely complex parts (hand-written tools, per-user on-behalf-of token flows) drop down to Python escape hatches the profile points at.

// profiles/mautic.json — a whole server, no Python
{
  "id": "mautic",
  "display_name": "BAUER GROUP Mautic",
  "backend": { "base_url": "${env:MAUTIC_URL}", "api_base_path": "/api" },
  "auth": {
    "inbound":  { "mode": "oidc" },
    "outbound": { "type": "bearer_env", "value_from_env": "MAUTIC_TOKEN" }
  },
  "tools": { "source": "openapi", "spec": { "source": "${env:MAUTIC_OPENAPI_URL}" } }
}

# src/main.py — the entire entrypoint
from bg_mcpcore import load_profile, make_cli

app = make_cli(load_profile("profiles/mautic.json"))
if __name__ == "__main__":
    app()

Install

Requires Python 3.12, 3.13, or 3.14.

From PyPI

pip install bg-mcpcore

Directly from GitHub

# Latest from main
pip install git+https://github.com/bauer-group/LIB-BG-MCPCore.git@main

# A specific released version/tag
pip install git+https://github.com/bauer-group/LIB-BG-MCPCore.git@v1.6.0

# With extras (any install method)
pip install "bg-mcpcore[openapi] @ git+https://github.com/bauer-group/LIB-BG-MCPCore.git@main"

Optional extras

pip install "bg-mcpcore[openapi]"                               # + OpenAPI-derived tools
pip install "bg-mcpcore[openapi,redis,tasks,oauth-providers]"   # full Shlink-shaped server

Architecture

• Pluggable via Python entry points — new auth_providers, tool_sources, auth_resolvers are pip-installable plugins, never core edits.
• Central tool registry — reusable tools (bg.health, …) referenced by name from any profile (tools.source: "registry").
• Fail-closed by design — AUTH_MODE=none forbidden in production; the JWT signing key mandatory for any active mode; invariants live in core.

See the documentation for the profile schema reference, plugin authoring guide, and security model.

License

MIT © BAUER GROUP