IMPLEMENTATIONS

ACC is independent of any one runtime.

A project can implement ACC as a parser, generator, runtime, gateway, SDK tool, policy engine, or full control plane.

REFERENCE IMPLEMENTATION

BailingHub proves the contract end to end.

BailingHub is the first open-source A2B control plane and reference implementation of ACC. It is listed here as an implementation, not as the definition of ACC itself.

BailingHub Reference implementation

Compiles OpenAPI ACC declarations and SDK-generated specs into a runtime tool model, then applies route allowlists, risk levels, approval intent, subject requirements, HMAC-signed tool calls, audit trails, traceability, runtime diagnostics, SDKs, and console workflows.

ACC parser

Reads and validates x-agent-capability.

ACC generator

Produces ACC-compatible OpenAPI declarations.

ACC runtime

Enforces scope, risk, subject, approval intent, audit, and execution hints.

ACC reference implementation

Maintained implementation used to prove the contract in practice.

IMPLEMENTATION TYPES

Compatible does not mean identical.

01

Control planes

Turn declarations into routed, audited, governable agent operations.

02

API gateways

Use ACC as policy metadata next to existing API contracts.

03

SDK generators

Produce ACC metadata from framework annotations or source code.

04

Policy engines

Validate risk, subject, approval, and audit declarations before runtime.