Stop wiring dozens of Model Context Protocol servers into every agent. Configure them once in Universal MCP Bridge, and your agent talks to a compact three-tool API — keeping its context small while reaching every backing server.
In a neutral benchmark, 756 tools wired directly into an agent consumed 138,417 tokens of static context — and at that scale the direct path is effectively unusable; agents degrade and can't ingest the set.
UMB hides that surface behind three meta-tools and serves full definitions only on request. The same 756 tools collapse to ~1,200 tokens.
The agent only ever sees list_tools, list_mcps, and route_mcp_call. UMB fans those out to every configured server and routes the call back.
Sees a 3-tool API. Tool list stays small and fast no matter how many servers sit behind it.
Add unlimited servers in servers.json. Edits hot-swap live — no restart.
Register all your MCP servers once in servers.json. UMB connects to each — stdio, HTTP, or SSE — and presents a single unified surface to the agent.
list_tools ranks results deterministically by name match, with optional semantic search. The agent pulls full schemas only for tools it needs via get_tool_info.
Edit servers.json while UMB is running and changes are picked up automatically. No restart, no dropped session.
Share one warm backend across many agent sessions. Lightweight proxies connect to a single daemon and forward MCP traffic.
A built-in diagnostic scans for and cleans up orphaned daemon processes. Local introspection only — zero telemetry, zero network.
Written in Rust. One 3–8 MB static binary, fast startup, no runtime dependencies. Build from source or grab a release.
NO TIERS · NO SERVER LIMITS · NO LICENSE KEYS · NO PHONE-HOME
UMB is a single Rust binary with no runtime dependencies. Clone and build, or download a prebuilt binary for macOS, Linux, or Windows.
Universal MCP Bridge (UMB) is a source-available gateway that sits in front of all your MCP servers. Instead of loading every server’s tools into your agent’s context, UMB exposes just three meta-tools — list_tools, list_mcps, and route_mcp_call — and reduces static tool context by about 99.1%.
UMB collapses a measured 138,417-token tool baseline into a compact 3-tool surface, a roughly 99.1% reduction in static tool context. In real agent sessions this translates to a 55%–75% reduction in working context.
Yes — UMB is free for noncommercial use under the PolyForm Noncommercial 1.0.0 license, with full source on GitHub. Commercial use requires a Team or Enterprise license; contact the maintainer.
Yes. UMB is a standard MCP server (JSON-RPC 2.0 over stdio), so it works with Claude Code and any MCP-compatible client. You register UMB once and it fronts every other MCP server.
Most MCP gateways focus on auth, governance, or consolidation. UMB leads on context efficiency: a single Rust binary with no feature gates that cuts static tool context ~99.1%, plus optional semantic tool search.
Read the source, run it everywhere, change what you need. Using UMB inside a company? A commercial license keeps you square — no key to install, just a contract.