Struct V2ForkSessionBuilder 

pub struct V2ForkSessionBuilder<Counterpart, Run = NullRun>
where
    Counterpart: HasPeer<Agent>,
    Run: RunWithConnectionTo<Counterpart>,
{ /* private fields */ }

Available on crate features unstable_protocol_v2 and unstable_session_fork only.

Builder for an unstable draft protocol v2 session/fork request.

A successful fork creates a new independent session whose ID comes from the v2::ForkSessionResponse. Register typed v2::UpdateSessionNotification and interactive request handlers on crate::Builder before connecting, then use Self::start_session to obtain a command handle for the fork or on_proxy_session_start to forward setup through a proxy.

This type is available with the unstable_session_fork feature. With unstable_mcp_over_acp as well, with_mcp_server attaches an MCP server to the forked session.

Implementations

impl<Counterpart, Run> V2ForkSessionBuilder<Counterpart, Run>

where Counterpart: HasPeer<Agent>, Run: RunWithConnectionTo<Counterpart>,

pub fn with_mcp_server<McpRun>( self, mcp_server: McpServer<Counterpart, McpRun>, ) -> Result<V2ForkSessionBuilder<Counterpart, ChainRun<Run, McpRun>>, Error>

where McpRun: RunWithConnectionTo<Counterpart>,

Available on crate feature unstable_mcp_over_acp only.

Attach an MCP server to this forked protocol v2 session.

This method is available when unstable_mcp_over_acp is enabled in addition to unstable_protocol_v2 and unstable_session_fork. MCP routes are installed and their runner tasks receive an initial poll before session/fork is published, allowing the agent to connect while handling session setup. A successful attachment remains active for the lifetime of the connection.

pub fn start_session( self, ) -> SentRequest<OpenedV2Session<Counterpart, ForkSessionResponse>>

where Run: 'static,

Send session/fork and return its independently consumable request.

The successful result contains both a cloneable command handle for the newly created fork and the complete v2::ForkSessionResponse. Consume the returned request with SentRequest::block_task, SentRequest::on_receiving_result, or another explicit SentRequest completion mode.

Attached MCP routes are installed and their runner tasks begin executing before the request is published. A valid success response promotes them to the connection lifetime independently from how this request handle is consumed; setup errors clean up the pending attachment.

pub fn on_proxy_session_start<F, Fut>( self, responder: Responder<ForkSessionResponse>, op: F, ) -> Result<(), Error>

where Counterpart: HasPeer<Client>, Run: 'static, F: FnOnce(OpenedV2Session<Counterpart, ForkSessionResponse>) -> Fut + Send + 'static, Fut: Future<Output = Result<(), Error>> + Send,

Fork a protocol v2 session through a proxy and forward its response.

The downstream request is ordered and inherits cancellation from the upstream request. On success, this helper obtains the new session ID from the response, installs session routing before later inbound traffic is processed, forwards the complete response, and spawns op with an OpenedV2Session containing the fork’s command handle and response. Inbound updates and interactive requests remain independent connection traffic.

The callback runs outside the ordered response barrier, so it may wait for later connection traffic without deadlocking the dispatch loop.

Trait Implementations

impl<Counterpart, Run> Debug for V2ForkSessionBuilder<Counterpart, Run>

where Counterpart: HasPeer<Agent> + Debug, Run: RunWithConnectionTo<Counterpart> + Debug,

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.