What causes "Task not found" in davila7/claude-code-templates?

Re-submit the task via POST /api/execute to get a fresh task ID

Task not found

Error message

Task not found

What it means

GET /api/task/:taskId looks up the task in the in-memory activeTasks Map and returns 404 when no task with that ID exists. Task IDs are only held in the server process's memory, so they disappear on restart and are never persisted.

Source

Thrown at cli-tool/src/sandbox-server.js:180

    // Execute based on mode
    if (mode === 'cloud') {
        executeE2BTask(task);
    } else {
        executeLocalTask(task);
    }
    
    res.json({
        success: true,
        taskId: taskId,
        message: 'Task started successfully'
    });
});

// API endpoint to get task status
app.get('/api/task/:taskId', (req, res) => {
    const task = activeTasks.get(req.params.taskId);
    if (!task) {
        return res.status(404).json({
            success: false,
            error: 'Task not found'
        });
    }
    
    res.json({
        success: true,
        task: {
            id: task.id,
            title: task.title,
            status: task.status,
            progress: task.progress,
            output: task.output.join('\\n'),
            startTime: task.startTime,
            endTime: task.endTime,
            sandboxId: task.sandboxId
        }
    });

View on GitHub (pinned to a0851ed10c)

Solutions

Re-submit the task via POST /api/execute to get a fresh task ID
Verify the task ID string exactly matches what /api/execute returned (task-<timestamp>-<random>)
Keep the same server process alive while polling, or persist tasks externally if cross-restart status is needed

Defensive patterns

Strategy: fallback

Validate before calling

const taskRes = await fetch(`${base}/api/task/${encodeURIComponent(taskId)}`);
if (taskRes.status === 404) {
  // task lost (server restart?) — resubmit
  const redo = await fetch(`${base}/api/execute`, { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({ prompt }) });
  const { taskId: newId } = await redo.json();
}

Try / catch

try { const r = await fetch(url); if (r.status === 404) { /* resubmit */ } } catch (e) { /* network error: retry with backoff */ }

Prevention

Store the task ID returned by /api/execute exactly and urlencode it
Don't restart the server while tasks are in flight
Treat 404 on polling as a signal to resubmit, not a hard failure

When it happens

Trigger: Polling /api/task/<id> with a malformed or wrong ID (e.g. missing the task- prefix generated by /api/execute); polling after the server restarted; polling a task created by a different server instance (multiple sandbox servers on different ports).

Common situations: Client resumes polling after a server restart; typos in task ID; load-balanced or redeployed server losing in-memory state; very long-running tasks where the client reconnects later.

Understand the failure class

Background: 'Could not be found', 'does not exist', 'not found in database': the resource-not-found family when an ID, slug, key, or URI lookup comes back empty — this error's family across 20 libraries.

Related errors

AI-assisted analysis of davila7/claude-code-templates@a0851ed10c (2026-08-28). Data as JSON: /api/errors/1eb36edba537a25b. Report an issue: GitHub.