Create fine-tuning jobs, monitor training runs, and deploy custom models on Together AI's
infrastructure. Use this workflow when you need to customize an open-source model on your
own data, track training metrics, manage model versions, or set up dedicated inference
endpoints for production. This is the secondary workflow — for basic inference and chat
completions, see together-core-workflow-a.
import Together from 'together-ai';
const client = new Together({ apiKey: process.env.TOGETHER_API_KEY });
const file = await client.files.upload({
file: fs.createReadStream('training.jsonl'),
purpose: 'fine-tune',
});
const job = await client.fineTuning.create({
training_file: file.id,
model: 'meta-llama/Llama-3.3-70B-Instruct-Turbo',
n_epochs: 3,
learning_rate: 1e-5,
batch_size: 4,
suffix: 'support-agent-v2',
});
console.log(`Fine-tune job ${job.id} — status: ${job.status}`);
let status = await client.fineTuning.retrieve(job.id);
while (!['completed', 'failed', 'cancelled'].includes(status.status)) {
console.log(`Status: ${status.status} — ${status.training_steps_completed}/${status.total_steps} steps`);
if (status.metrics) console.log(` Loss: ${status.metrics.training_loss.toFixed(4)}`);
await new Promise(r => setTimeout(r, 30_000));
status = await client.fineTuning.retrieve(job.id);
}
console.log(`Final model: ${status.fine_tuned_model}`);
const models = await client.models.list({ owned_by: 'me' });
models.data.forEach(m =>
console.log(`${m.id} — created ${m.created_at}, type: ${m.type}`)
);
// Delete an old model version
await client.models.delete('my-org/support-agent-v1');
console.log('Deleted old model version');
const endpoint = await client.endpoints.create({
model: status.fine_tuned_model,
instance_type: 'gpu-a100-80gb',
min_replicas: 1,
max_replicas: 3,
autoscale_target_utilization: 0.7,
});
console.log(`Endpoint ${endpoint.id} — URL: ${endpoint.url}`);
console.log(`Status: ${endpoint.status}, replicas: ${endpoint.current_replicas}`);
| Issue | Cause | Fix |
|---|---|---|
401 Unauthorized |
Invalid or expired API key | Regenerate at api.together.xyz/settings |
400 Invalid JSONL |
Malformed training file | Each line must be valid JSON with messages array |
422 Model not fine-tunable |
Model does not support fine-tuning | Check supported models at docs.together.ai |
429 Rate limited |
Too many requests per minute | Implement exponential backoff with 1s base |
| Training job failed | Data quality or OOM error | Reduce batch_size or check file format |
A successful workflow uploads training data, monitors a fine-tuning job to completion, and deploys the custom model to an autoscaling dedicated endpoint for production.
See together-sdk-patterns for client initialization and batch inference helpers.