# Run & Streaming
## Stateless run
For one-off requests without session persistence:
```http
POST /run
Content-Type: application/json
{
"goal": "What files are in the current directory?",
"system_prompt": "You are a helpful assistant.",
"max_steps": 10
}
```
**Response** (JSON):
```json
{
"status": "finished",
"finish_reason": "NoMoreToolCalls",
"messages": [...],
"usage": { "total_steps": 2, "total_tokens": 640 }
}
```
## Session run (SSE streaming)
Send a message to an existing session and subscribe to Server-Sent Events on the `/sessions/:id/events` endpoint:
```http
POST /sessions/:id/run
Content-Type: application/json
{ "goal": "List the files in src/" }
```
Then consume the SSE stream on `/sessions/:id/events`:
```
event: tool_call
data: {"name":"list_dir","step":1}
event: tool_result
data: {"name":"list_dir","success":true}
event: message
data: {"role":"assistant","content":[{"type":"text","text":"The src/ directory contains..."}]}
event: done
data: {"finish_reason":"NoMoreToolCalls","total_steps":1}
```
## SSE event types
| `message` | `{ role, content: ContentBlock[] }` |
| `partial_message` | `{ text, step }` — streaming text delta |
| `tool_call` | `{ name, step }` |
| `tool_result` | `{ name, success }` |
| `done` | `{ finish_reason, total_steps }` |
| `error` | `{ message }` |
| `plan_proposed` | `{ plan }` — agent awaiting plan approval |
## Consuming SSE in JavaScript
```javascript
// First POST to trigger the run
await fetch('/sessions/abc123/run', {
method: 'POST',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify({ goal: 'list files' }),
});
// Then subscribe to events
const evtSource = new EventSource('/sessions/abc123/events');
evtSource.addEventListener('tool_call', (e) => {
const data = JSON.parse(e.data);
console.log(`[tool] ${data.name}`);
});
evtSource.addEventListener('message', (e) => {
const data = JSON.parse(e.data);
for (const block of data.content) {
if (block.type === 'text') console.log(block.text);
}
});
evtSource.addEventListener('done', (e) => {
const data = JSON.parse(e.data);
console.log('Done:', data.finish_reason);
evtSource.close();
});
```
## Consuming SSE in Python
```python
import json, sseclient, requests
# Trigger the run
requests.post(
'http://localhost:3000/sessions/abc123/run',
json={'goal': 'list files'},
)
# Subscribe to events
resp = requests.get(
'http://localhost:3000/sessions/abc123/events',
stream=True,
)
client = sseclient.SSEClient(resp)
for event in client.events():
data = json.loads(event.data)
if event.event == 'message':
for block in data.get('content', []):
if block.get('type') == 'text':
print(block['text'])
elif event.event == 'done':
print('Done:', data['finish_reason'])
break
```