Struct PluginToolAdapter 

pub struct PluginToolAdapter { /* private fields */ }

An AgentTool backed by a plugin’s 4-function handle. One adapter is built per registered tool (schema copied from the registration) and inserted into the session’s tool set in B2.

Holds a clone of the session’s PluginKeepalive so the cdylib that owns handle’s fn pointers stays mapped for as long as the adapter (and thus any in-flight execute) may call them. Without this the Library could drop (unload the cdylib) while a fn pointer is still callable → UAF. The keepalive is Arc-shared with every other adapter built from the same session, so the last drop — which can only happen once the harness’s tool vec drops — unloads.

Implementations

impl PluginToolAdapter

pub fn new( schema: Tool, handle: PluginToolHandle, keepalive: Arc<PluginKeepalive>, ) -> Self

Build an adapter from the registered schema + handle + the session’s keepalive. label defaults to the tool name. The keepalive clone keeps the owning cdylib mapped for the adapter’s lifetime.

pub fn with_context(self, context: ToolCallContext) -> Self

Attach the session’s context, so each call carries cwd + sessionId. Builder-style so the three-argument PluginToolAdapter::new keeps working for callers that have no session (tests, the SDK smoke test).

Trait Implementations

impl AgentTool for PluginToolAdapter

fn schema(&self) -> &Tool

The provider-facing tool definition (name, description, parameters schema).

fn label(&self) -> &str

Human-readable label for UI display.

fn execution_mode(&self) -> ToolExecutionMode

Per-tool execution-mode override. Sequential forces one-at-a-time for the whole batch when any tool in it returns Sequential; Parallel (default) allows concurrency.

fn execute<'life0, 'life1, 'async_trait>( &'life0 self, tool_call_id: &'life1 str, params: Value, signal: CancellationToken, on_update: Arc<dyn Fn(ToolResultPartial) + Send + Sync>, ) -> Pin<Box<dyn Future<Output = Result<AgentToolResult, AgentError>> + Send + 'async_trait>>

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

Execute the tool call. Throw via Err(AgentError) on failure — the loop encodes the error message into an error ToolResultMessage.

fn prepare_arguments(&self, args: Value) -> Result<Value, AgentError>

Optional compatibility shim for raw tool-call arguments before schema validation. Default is identity. Mirrors TS prepareArguments.