minibridge

Minibridge acts as a secure, configurable bridge between MCP servers and clients. It wraps an MCP server (for example, an existing uvx-based MCP server) and can apply policy enforcement, telemetry, and monitoring, while optionally performing SBOM generation and validation. Minibridge also supports OpenTelemetry integration and can operate in an all-in-one (AIO) mode where the bridge and the downstream MCP server run in a single process, simplifying deployment. To use it, configure Minibridge as the entry point in your MCP client configuration, replacing direct commands to the MCP server with a Minibridge invocation, for example by routing the downstream server through the bridge using the aio mode.

In practice you typically set up a configuration entry that points to Minibridge as the top-level command, and pass the original MCP server command as an argument to Minibridge. Minibridge then manages the execution of the downstream MCP server inside its controlled environment, enabling integrity checks, policing, and telemetry. Beyond the AIO mode, Minibridge can coordinate with Policers (local Rego or remote HTTP policies) to authenticate agents, analyze content, and transform requests or responses as needed. The platform also exposes Prometheus metrics and supports OTLP tracing for observability.

Prerequisites:

• a supported OS (Linux, macOS, or Windows) and a compatible runtime environment
• network access to fetch or build the Minibridge binary

Install options:

1. Install via Homebrew (macOS):

brew tap acuvity/tap
brew install minibridge

2. Install via AUR (Arch Linux):

yay -S minibridge

To use the latest version from the main branch:

yay -S minibridge-git

3. Install via Go (source or module-aware):

go install go.acuvity.ai/minibridge@latest

Or, for the main branch:

go install go.acuvity.ai/minibridge@main

4. Manual binary download:

• Download the release binary from the Minibridge releases page and place it in your PATH.
• Ensure the binary is executable: chmod +x minibridge.

Usage example after installation:

# Example: run Minibridge in AIO mode wrapping a downstream MCP server
minibridge aio -- uvx mcp-server-fetch

Notes and tips:

• If you see errors like MCP fetch: spawn minibridge ENOENT, ensure the command parameter points to the correct full path of the Minibridge binary (use which minibridge to verify).
• In AIO mode, Minibridge wraps the downstream MCP process; ensure the downstream command (e.g., uvx mcp-server-fetch) is accessible to Minibridge in the same environment.
• For TLS and client-certificate validation, configure Minibridge’s TLS settings and policies as needed via your deployment configuration.
• If you plan to enable Policers, decide whether to implement local Rego-based policies or remote HTTP policies and configure the appropriate endpoints.
• Enable telemetry (Prometheus, OTEL) by wiring the metrics and tracing endpoints in your deployment environment.