# What changed in agent-client-protocol

> 6 changes in agent-client-protocol 0.11 to 0.12 from its official release notes, upgrade guides and advisories: 2 new APIs and options. Each one cited. Sources checked 2026-10-19. HTML: https://unstale.sh/pypi/agent-client-protocol/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## agent-client-protocol 0.12

### New APIs and options

- An ACP HTTP and WebSocket web transport implementation is now available. (0.12.0) — [release notes](https://github.com/agentclientprotocol/python-sdk/releases/tag/0.12.0)
- The ACP schema now supports extensible unions, allowing unions to accommodate extensions. (0.12.0) — [release notes](https://github.com/agentclientprotocol/python-sdk/releases/tag/0.12.0)

### Behavior and default changes

- The ACP schema now supports lenient deserialization. (0.12.0) — [release notes](https://github.com/agentclientprotocol/python-sdk/releases/tag/0.12.0)

### Fixes and other changes

- Code generation now supports datamodel-code-generator 0.71. (0.12.1) — [release notes](https://github.com/agentclientprotocol/python-sdk/releases/tag/0.12.1)
- Notification response ordering is preserved. (0.12.1) — [release notes](https://github.com/agentclientprotocol/python-sdk/releases/tag/0.12.1)

## agent-client-protocol 0.11

### Fixes and other changes

- Unhandled RPC handler exceptions are now logged, making them easier to diagnose. (0.11.1) — [release notes](https://github.com/agentclientprotocol/python-sdk/releases/tag/0.11.1)