# What changed in @agentclientprotocol/sdk

> 10 changes in @agentclientprotocol/sdk 2 from its official release notes, upgrade guides and advisories: 5 breaking. Each one cited. Sources checked 2026-10-28. HTML: https://unstale.sh/npm/@agentclientprotocol/sdk/

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

## @agentclientprotocol/sdk 2

### Breaking changes

- Default v1 imports expose only stable-feature schemas; use this subpath for unstable v1 features. (2.0.0) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.0)
- AgentSideConnection, ClientSideConnection, Agent, Client, LegacyAgentFactory, createLegacyAgent, their extension aliases, and the connector helper have been removed. Use agent()/client() apps and peer-context request()/notify() calls. (2.0.0) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.0)
- Compiled tests, fixtures, and examples are no longer published. (2.0.0) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.0)
- The unversioned JSON schema export is removed; use the versioned schema/v1 or schema/v2 exports. (2.0.0) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.0)
- The supported Zod floor is enforced. (2.0.0) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.0)

### Performance

- Zod is imported as a namespace so bundlers can tree-shake it. (2.0.0) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.0)

### Behavior and default changes

- Default experimental v2 imports expose only stable-feature schemas; use this subpath for unstable v2 features. (2.0.0) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.0)

### Fixes and other changes

- HTTP POST failures are isolated to their request scope. (2.0.2) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.2)
- SSE streams now handle CR line endings. (2.0.2) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.2)
- Session stream conflicts are isolated from the shared transport. (2.0.1) — [release notes](https://github.com/agentclientprotocol/typescript-sdk/releases/tag/v2.0.1)