Start a training run

Viewing v1— superseded by v2

POST

/v1/workspaces/{workspace_id}/training-runs

curl --request POST \
  --url https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "reference_set_id": "<uuid>",
  "base_model_id": "<string>",
  "training_framework": "fal",
  "webhook": {
    "url": "<string>",
    "events": [
      "inference.completed"
    ],
    "metadata": {}
  }
}'

import requests

url = "https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs"

payload = {
    "reference_set_id": "<uuid>",
    "base_model_id": "<string>",
    "training_framework": "fal",
    "webhook": {
        "url": "<string>",
        "events": ["inference.completed"],
        "metadata": {}
    }
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())

const url = 'https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"reference_set_id":"<uuid>","base_model_id":"<string>","training_framework":"fal","webhook":{"url":"<string>","events":["inference.completed"],"metadata":{}}}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}

package main

import (
  "fmt"
  "strings"
  "net/http"
  "io"
)

func main() {

  url := "https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs"

  payload := strings.NewReader("{\n  \"reference_set_id\": \"<uuid>\",\n  \"base_model_id\": \"<string>\",\n  \"training_framework\": \"fal\",\n  \"webhook\": {\n    \"url\": \"<string>\",\n    \"events\": [\n      \"inference.completed\"\n    ],\n    \"metadata\": {}\n  }\n}")

  req, _ := http.NewRequest("POST", url, payload)

  req.Header.Add("Authorization", "Bearer <token>")
  req.Header.Add("Content-Type", "application/json")

  res, _ := http.DefaultClient.Do(req)

  defer res.Body.Close()
  body, _ := io.ReadAll(res.Body)

  fmt.Println(res)
  fmt.Println(string(body))

}

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'reference_set_id' => '<uuid>',
    'base_model_id' => '<string>',
    'training_framework' => 'fal',
    'webhook' => [
        'url' => '<string>',
        'events' => [
                'inference.completed'
        ],
        'metadata' => [

        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

OkHttpClient client = new OkHttpClient();

MediaType mediaType = MediaType.parse("application/json");
RequestBody body = RequestBody.create(mediaType, "{\n  \"reference_set_id\": \"<uuid>\",\n  \"base_model_id\": \"<string>\",\n  \"training_framework\": \"fal\",\n  \"webhook\": {\n    \"url\": \"<string>\",\n    \"events\": [\n      \"inference.completed\"\n    ],\n    \"metadata\": {}\n  }\n}");
Request request = new Request.Builder()
  .url("https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs")
  .post(body)
  .addHeader("Authorization", "Bearer <token>")
  .addHeader("Content-Type", "application/json")
  .build();

Response response = client.newCall(request).execute();

require 'uri'
require 'net/http'

url = URI("https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"reference_set_id\": \"<uuid>\",\n  \"base_model_id\": \"<string>\",\n  \"training_framework\": \"fal\",\n  \"webhook\": {\n    \"url\": \"<string>\",\n    \"events\": [\n      \"inference.completed\"\n    ],\n    \"metadata\": {}\n  }\n}"

response = http.request(request)
puts response.read_body

var client = new RestClient("https://api.app.layer.ai/api/v1/workspaces/:workspace_id/training-runs");
var request = new RestRequest("", Method.Post);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"reference_set_id\": \"<uuid>\",\n  \"base_model_id\": \"<string>\",\n  \"training_framework\": \"fal\",\n  \"webhook\": {\n    \"url\": \"<string>\",\n    \"events\": [\n      \"inference.completed\"\n    ],\n    \"metadata\": {}\n  }\n}", ParameterType.RequestBody);
var response = client.Execute(request);

v1 is superseded. v1 was superseded by v2 on 2026-08-26. A sunset date has not been announced yet; v1 will be deprecated as a whole before removal. Migrate with the v2 migration guide.

Start training a custom style/LoRA from a reference set. Returns immediately with a run ID. Poll GET /workspaces/{workspace_id}/training-runs/{training_run_id} for progress. Creative Units are reserved at submission; call the estimate endpoint first to check cost.

Authorizations

bearerAuth
oauth2
serviceAccount
reference_sets:write

Parameters

Path Parameters

workspace_id

required

Workspace Id

Id of the workspace that owns the resource.

string format: uuid

Id of the workspace that owns the resource.

Header Parameters

Idempotency-Key

string

<= 255 characters

Opaque key making a retry of this request return the first result. A 2xx response is replayed for 24 hours with Idempotent-Replayed: true. A 4xx releases the key. A 5xx, or a request still running, holds the key for 120 seconds, during which a retry gets 409; after that a retry executes again. The key covers the method, path, query, and byte-identical body it was first used with; reusing it for a different request is rejected with 422. Protection is best effort: if the key store is unavailable, or a record is lost early, a retry can execute again even after an earlier 409. See the Idempotency section of the API description.

Request Body^required

application/json

StartTrainingRequest

object

reference_set_id

required

Reference Set Id

The reference set (Style) to train a LoRA for.

string format: uuid

base_model_id

Base Model Id

Base model to train. Omit to use the reference set’s configured or workspace default model.

string

nullable

training_framework

Training Framework

Training framework override. Omit for the server default.

string

nullable

Allowed values: fal ai-toolkit

webhook

Any of:

WebhookInput
null

WebhookInput

Where to POST this request’s terminal events, and what to include with them.

object

url

required

Url

HTTPS URL that receives a POST when this request reaches a terminal state. Must be publicly reachable; must not redirect. Acknowledge with any 2xx within 10 seconds and do the work asynchronously. Reply 410 to stop delivery permanently.

string

<= 2048 characters

events

Events

Narrows what is delivered. Omit to receive every event this request can produce, which is what expected_events on the response lists.

Array<string>

nullable

Allowed values: inference.completed inference.failed inference.cancelled training.succeeded training.failed scoring_run.completed scoring_run.failed workflow_run.succeeded workflow_run.failed workflow_run.cancelled

metadata

Metadata

Opaque key/value pairs echoed back verbatim in every delivery, for correlating a callback with your own records. At most 10 keys and 1024 bytes in total.

object

key

additional properties

string

Responses

202

Successful Response

application/json

StartTrainingResponse

object

training_run_id

required

Training Run Id

Unique identifier for this training run.

string format: uuid

state

required

State

Coarse state; in_progress right after submission.

string

Allowed values: in_progress terminal_success terminal_failure

raw_status

required

Raw Status

Fine-grained run status (e.g. initializing).

string

base_model_id

Base Model Id

Base model the run trains with.

string

nullable

created_at

required

Created At

Timestamp the run was created.

string format: date-time

poll_interval_seconds

required

Poll Interval Seconds

Suggested polling interval in seconds.

integer

expected_events

Expected Events

Deliveries this run will produce. Empty when no webhook was supplied.

Array<string>

default:

Example

{
  "state": "in_progress",
  "expected_events": []
}

401

Unauthenticated — missing or invalid Bearer token.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

403

Forbidden — insufficient permissions, or the access token lacks the scope the operation requires.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

404

Resource not found.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

409

The outcome of the request with this Idempotency-Key is not known yet: it is still running, or it failed without a stored response. Retry after the number of seconds in Retry-After.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

422

Invalid input parameters, or an Idempotency-Key reused for a different request.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

429

Rate limited — retry after the number of seconds in Retry-After.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

500

Internal server error.

application/problem+json

object

type

required

string

title

required

string

status

required

integer

detail

required

string

Example

{
  "type": "https://api.layer.ai/errors/ERROR_CODE",
  "title": "Error Title",
  "status": 400,
  "detail": "Human-readable description."
}

Start a training run

Authorizations

Parameters

Path Parameters

Header Parameters

Request Bodyrequired

Responses

202

Example

401

Example

403

Example

404

Example

409

Example

422

Example

429

Example

500

Example

Request Body^required