Busbar

About Busbar

Busbar is the self-hosted execution boundary for AI systems. AI now takes action: model calls invoke tools, agents delegate work, and every hop can carry authority, credentials, cost, data, and trust risk. Busbar governs those actions before they leave your environment. For traffic routed through Busbar, it: • Admits requests by checking identity, grants, budgets, and trust before dispatch. • Governs execution with policy, credential custody, and request-path hooks. • Executes through approved protocol, routing, resilience, and evidence paths. Busbar covers three execution planes: • Model control — Keep supported native SDK workflows while centralizing model access, provider credentials, routing, budgets, circuit breaking, failover, and telemetry. • Tool governance — Treat MCP tool calls as execution events. Authenticate callers, enforce grants and budgets, validate approved schemas, and quarantine tools when their approved contract drifts. • Agent trust — Verify, pin, and re-check remote A2A agent identity. Enforce configured egress scopes and use target-bound leased credentials rather than forwarding caller credentials downstream. One static Rust binary. Self-hosted. Customer-operated. No runtime or sidecar. Private and air-gap deployable. Apache-2.0 open source. Control what AI can do before it acts. https://getbusbar.com