Struct CallbackMiddleware 

pub struct CallbackMiddleware { /* private fields */ }

Adapts a CallbackHandler into an AgentMiddleware.

This allows any callback handler (e.g., OpenTelemetryCallback, RecordingCallback) to be used in the middleware stack of a Deep Agent or graph agent that only accepts Vec<Arc<dyn AgentMiddleware>>.

The adapter fires lifecycle events at each middleware hook:

• before_agent → RunEvent::RunStarted
• after_agent → RunEvent::RunFinished
• before_model → RunEvent::BeforeMessage
• after_model → RunEvent::LlmCalled

Implementations

impl CallbackMiddleware

pub fn new(handler: Arc<dyn CallbackHandler>) -> Self

Create a new adapter wrapping the given callback handler.

pub fn with_run_id(handler: Arc<dyn CallbackHandler>, run_id: String) -> Self

Create with a specific run ID (useful for correlating spans).

Trait Implementations

impl AgentMiddleware for CallbackMiddleware

fn before_agent<'life0, 'life1, 'async_trait>( &'life0 self, _messages: &'life1 mut Vec<Message>, ) -> Pin<Box<dyn Future<Output = Result<(), SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Called once when the agent starts executing.

fn after_agent<'life0, 'life1, 'async_trait>( &'life0 self, messages: &'life1 mut Vec<Message>, ) -> Pin<Box<dyn Future<Output = Result<(), SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Called once when the agent finishes executing.

fn before_model<'life0, 'life1, 'async_trait>( &'life0 self, request: &'life1 mut ModelRequest, ) -> Pin<Box<dyn Future<Output = Result<(), SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Called before each model invocation. Can modify the request.

fn after_model<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, _request: &'life1 ModelRequest, response: &'life2 mut ModelResponse, ) -> Pin<Box<dyn Future<Output = Result<(), SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Called after each model invocation. Can modify the response.

fn wrap_model_call<'life0, 'life1, 'async_trait>( &'life0 self, request: ModelRequest, next: &'life1 dyn ModelCaller, ) -> Pin<Box<dyn Future<Output = Result<ModelResponse, SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Wraps the model call. Override to intercept or replace the model invocation.

fn wrap_tool_call<'life0, 'life1, 'async_trait>( &'life0 self, request: ToolCallRequest, next: &'life1 dyn ToolCaller, ) -> Pin<Box<dyn Future<Output = Result<Value, SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Wraps a tool call. Override to intercept or replace tool execution.

fn before_file_op<'life0, 'life1, 'async_trait>( &'life0 self, _op: &'life1 FileOp, ) -> Pin<Box<dyn Future<Output = Result<FileOpDecision, SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Called before a file operation. Return Deny to block it.

fn after_file_op<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, _op: &'life1 FileOp, _result: &'life2 FileOpResult, ) -> Pin<Box<dyn Future<Output = Result<(), SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Called after a file operation completes.

fn before_command<'life0, 'life1, 'async_trait>( &'life0 self, _cmd: &'life1 CommandOp, ) -> Pin<Box<dyn Future<Output = Result<CommandDecision, SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Called before a shell command. Return Deny to block it.

fn after_command<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, _cmd: &'life1 CommandOp, _result: &'life2 CommandResult, ) -> Pin<Box<dyn Future<Output = Result<(), SynapticError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Called after a shell command completes.