@sf-build/rpc-client
Standalone RPC client SDK for SF. Spawn the agent process, perform a v2 protocol handshake, send commands, and consume typed events via an async generator — all in a few lines of TypeScript.
Zero internal dependencies. Ships its own inlined types.
Installation
npm install @sf-build/rpc-client
Quick Start
import { RpcClient } from '@sf-build/rpc-client';
const client = new RpcClient({ cwd: process.cwd() });
await client.start();
const { sessionId } = await client.init({ clientId: 'my-app' });
console.log(`Session: ${sessionId}`);
await client.prompt('Create a hello world script');
for await (const event of client.events()) {
if (event.type === 'execution_complete') break;
console.log(event.type);
}
await client.shutdown();
API
Constructor
const client = new RpcClient(options?: RpcClientOptions);
| Option |
Type |
Description |
cliPath |
string |
Path to the CLI entry point |
cwd |
string |
Working directory for the agent |
env |
Record<string, string> |
Environment variables |
provider |
string |
AI provider (e.g. "anthropic") |
model |
string |
Model ID (e.g. "claude-sonnet") |
args |
string[] |
Additional CLI arguments |
Lifecycle
| Method |
Description |
start() |
Spawn the agent process |
init(opts?) |
v2 handshake — returns sessionId, capabilities |
shutdown() |
Graceful shutdown |
stop() |
Force-kill the process |
Commands
| Method |
Description |
prompt(message, images?) |
Send a prompt |
steer(message, images?) |
Interrupt with a steering message |
followUp(message, images?) |
Queue a follow-up message |
abort() |
Abort current operation |
subscribe(events) |
Subscribe to event types (["*"] for all) |
Events
// Async generator — recommended
for await (const event of client.events()) {
console.log(event.type);
}
// Callback-based
const unsubscribe = client.onEvent((event) => {
console.log(event.type);
});
Helpers
| Method |
Description |
waitForIdle(timeout?) |
Wait for agent_end event |
collectEvents(timeout?) |
Collect events until idle |
promptAndWait(message, images?, t?) |
Send prompt and collect events |
Session & Model
| Method |
Description |
getState() |
Get session state |
setModel(provider, modelId) |
Set model |
cycleModel() |
Cycle to next model |
getAvailableModels() |
List available models |
setThinkingLevel(level) |
Set thinking level |
cycleThinkingLevel() |
Cycle thinking level |
compact(instructions?) |
Compact session context |
getSessionStats() |
Get session statistics |
bash(command) |
Execute a bash command |
newSession(parent?) |
Start a new session |
sendUIResponse(id, response) |
Respond to extension UI requests |
Type Exports
All protocol types are exported from the package root:
import type {
RpcCommand,
RpcResponse,
RpcInitResult,
RpcExecutionCompleteEvent,
RpcCostUpdateEvent,
RpcV2Event,
SessionStats,
SdkAgentEvent,
RpcClientOptions,
} from '@sf-build/rpc-client';
License
MIT
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