a2a-wrapper

A monorepo of A2A protocol wrappers that turn production AI backends into standalone, interoperable agents. Drop a JSON config file in, get a fully spec-compliant A2A server out.

The pattern: MCP is the vertical rail — how agents access tools. A2A is the horizontal rail — how agents talk to each other. This repo adds the horizontal rail to multiple AI backends.

Packages

Package	npm	Description
@a2a-wrapper/core		Shared infrastructure — logging, config loading, event publishing, server factory, session management, CLI scaffold
a2a-copilot		A2A wrapper for GitHub Copilot SDK
a2a-opencode		A2A wrapper for OpenCode (Anthropic, OpenAI, GitHub Copilot, and more)

Architecture

┌─────────────────────────────────────────────────────┐
│                  @a2a-wrapper/core                   │
│  Logger · Config · Events · Server · Session · CLI  │
└──────────────┬──────────────────────┬───────────────┘
               │                      │
       ┌───────▼───────┐      ┌───────▼───────┐
       │  a2a-copilot  │      │ a2a-opencode  │
       │  (Copilot SDK)│      │  (OpenCode)   │
       └───────┬───────┘      └───────┬───────┘
               │                      │
         GitHub Copilot          OpenCode Server

Each wrapper implements a single A2AExecutor interface and a thin config/CLI layer. Everything else — A2A protocol compliance, Express server wiring, agent card building, session TTL management — comes from @a2a-wrapper/core.

Quick Start

# Clone the monorepo
git clone https://github.com/shashikanth-gs/a2a-wrapper.git
cd a2a-wrapper

# Install all dependencies
npm install

# Run a specific wrapper
cd a2a-copilot
npm run dev -- --config agents/example/config.json

# Or
cd a2a-opencode
npm run dev -- --config agents/example/config.json

Development

This monorepo uses npm workspaces, Turborepo for task orchestration, and Changesets for versioning.

# Install dependencies for all packages
npm install

# Build all packages (core builds first, then wrappers in parallel)
npx turbo run build

# Run tests across all packages
npx turbo run test

# Type-check all packages
npx turbo run typecheck

# Clean build artifacts
npx turbo run clean

Turborepo caches build outputs — unchanged packages are skipped on subsequent runs.

Working on a Specific Package

You can scope Turborepo to a single package with --filter:

# Build only core
npx turbo run build --filter=@a2a-wrapper/core

# Test only a2a-copilot
npx turbo run test --filter=a2a-copilot

# Build a2a-opencode and its dependencies
npx turbo run build --filter=a2a-opencode...

Changesets Workflow

Every PR that changes package behavior should include a changeset:

# Create a new changeset (interactive prompt)
npx changeset

The CLI will ask which packages were affected, the semver bump type (patch / minor / major), and a summary. Commit the generated file with your PR. When the PR merges, the Changesets GitHub Action opens a "Version Packages" PR that batches pending bumps. Merging that PR publishes the updated packages to npm.

Adding a New Wrapper

Adding a new A2A wrapper (e.g. a2a-claude) requires no changes to the root config or core package:

1. Create the directory at the repo root following the a2a-<name> naming convention:

   a2a-claude/
   ├── package.json
   ├── tsconfig.json
   ├── src/
   │   ├── index.ts
   │   ├── cli.ts
   │   └── claude/
   │       ├── executor.ts       # Implements A2AExecutor
   │       ├── session-manager.ts
   │       └── config/
   │           ├── types.ts      # Extends BaseAgentConfig
   │           └── defaults.ts
   └── agents/
       └── example/
           └── config.json
   

2. Implement the A2AExecutor interface from @a2a-wrapper/core. This is the only interface your wrapper needs — it handles task execution for your backend. Define your backend config type extending BaseAgentConfig<YourBackend> and set up config defaults.

3. Wire it up with createCli() from @a2a-wrapper/core to get a fully functional CLI with config loading, server startup, and agent card generation out of the box.

4. Set up package.json with:

   • name set to a2a-<name>
   • @a2a-wrapper/core as a dependency ("*")
   • publishConfig.access set to "public"
   • build, test, and typecheck scripts

5. Run npm install at the repo root to link the new package. The a2a-* workspace glob in the root package.json automatically picks up the new directory.

6. Verify everything works:

   npx turbo run build test typecheck

7. Create a changeset for the initial release:

   npx changeset

See the core package README for the full API guide.

Contributing

Contributions are welcome! Please read CONTRIBUTING.md first.

License

MIT © Shashi Kanth