Struct PluginApi 

#[repr(C)]
pub struct PluginApi {

    pub abi_version: u32,
    pub struct_size: u32,
    pub free_string: FreeStringFn,
    pub register_tool: Option<extern "C" fn(schema: *const StableToolSchema, execute_fn: ToolExecuteFn, poll_fn: ToolPollFn, cancel_fn: ToolCancelFn, destroy_fn: ToolDestroyFn, plugin_free_string: FreeStringFn) -> i32>,
    pub register_command: Option<extern "C" fn(name: StbStringRef, description: StbStringRef, handler: CommandHandlerFn) -> i32>,
    pub register_shortcut: Option<extern "C" fn(key: StbStringRef, description: StbStringRef) -> i32>,
    pub register_flag: Option<extern "C" fn(name: StbStringRef, description: StbStringRef) -> i32>,
    pub register_provider: Option<extern "C" fn(provider_id: StbStringRef, base_url: StbStringRef, api_style: StbStringRef, request_fn: ProviderRequestFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>,
    pub register_message_renderer: Option<extern "C" fn(name: StbStringRef, render_fn: RenderFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>,
    pub register_markdown_transformer: Option<extern "C" fn(name: StbStringRef, render_fn: RenderFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>,
    pub register_entry_renderer: Option<extern "C" fn(name: StbStringRef, render_fn: RenderFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>,
    pub register_event_handler: Option<extern "C" fn(tag: EventTag, handler: EventHandlerFn, user_data: *mut c_void) -> i32>,
    pub register_resources_discover: Option<extern "C" fn(handler: ResourcesDiscoverFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>,
    pub runtime_action: RuntimeActionFn,
    pub dispatch_event: Option<extern "C" fn(event: StablePluginEvent, user_data: *mut c_void) -> i32>,
    pub user_data: *mut c_void,
    pub declare: Option<extern "C" fn(json: StbStringRef) -> i32>,
    pub register_before_agent_start: Option<extern "C" fn(handler: BeforeAgentStartFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>,
}

The host-provided API struct. The first two fields (abi_version and struct_size) are contract-identity markers that survive future signature changes: a plugin reads them from the pointer before anything else, so even if the entrypoint arity changes, the version check remains robust.

Fields

abi_version: u32

Contract identity. First field so a plugin can validate before reading anything else, independent of the entrypoint arity.

struct_size: u32

sizeof(PluginApi) as the host built it. Lets a plugin detect a host that predates slots it wants (host_struct_size < plugin’s expected offset). Future hosts may grow this struct; old plugins check struct_size before accessing new fields.

free_string: FreeStringFn

Host’s free_string — the plugin calls this for every StbString it receives from the host (outputs of actions, event payloads, inputs to execute). Never null.

register_tool: Option<extern "C" fn(schema: *const StableToolSchema, execute_fn: ToolExecuteFn, poll_fn: ToolPollFn, cancel_fn: ToolCancelFn, destroy_fn: ToolDestroyFn, plugin_free_string: FreeStringFn) -> i32>

register_command: Option<extern "C" fn(name: StbStringRef, description: StbStringRef, handler: CommandHandlerFn) -> i32>

register_shortcut: Option<extern "C" fn(key: StbStringRef, description: StbStringRef) -> i32>

register_flag: Option<extern "C" fn(name: StbStringRef, description: StbStringRef) -> i32>

register_provider: Option<extern "C" fn(provider_id: StbStringRef, base_url: StbStringRef, api_style: StbStringRef, request_fn: ProviderRequestFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>

register_message_renderer: Option<extern "C" fn(name: StbStringRef, render_fn: RenderFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>

register_markdown_transformer: Option<extern "C" fn(name: StbStringRef, render_fn: RenderFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>

register_entry_renderer: Option<extern "C" fn(name: StbStringRef, render_fn: RenderFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>

register_event_handler: Option<extern "C" fn(tag: EventTag, handler: EventHandlerFn, user_data: *mut c_void) -> i32>

register_resources_discover: Option<extern "C" fn(handler: ResourcesDiscoverFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>

runtime_action: RuntimeActionFn

dispatch_event: Option<extern "C" fn(event: StablePluginEvent, user_data: *mut c_void) -> i32>

user_data: *mut c_void

declare: Option<extern "C" fn(json: StbStringRef) -> i32>

Declare this plugin’s host-side preferences as a JSON object, e.g. {"priority":60,"platforms":["linux","macos"]}. Nullable: host does not support declarations yet (plugin skips the call; host applies defaults: priority 100, all platforms).

register_before_agent_start: Option<extern "C" fn(handler: BeforeAgentStartFn, plugin_free_string: FreeStringFn, user_data: *mut c_void) -> i32>

Register a system-prompt transformer for the run (pi’s before_agent_start returning systemPrompt).

Appended last on purpose. A plugin compiled against a shorter PluginApi indexes every earlier field by offset, so a slot inserted in the middle would make an old plugin read the new host’s fields at the wrong offsets. Appending keeps every existing offset valid, which is what lets this ship without an ABI version bump; a plugin checks struct_size (or the slot for None) before using it.

Nullable: a host that predates this slot leaves it None, the plugin skips the call, and the prompt is left alone — exactly that host’s behavior before this slot existed.

Trait Implementations

impl Clone for PluginApi

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for PluginApi

impl Send for PluginApi

impl Sync for PluginApi