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POST
POST /v1/training/jobs/{job_id}/forward-backward Computes the loss of a batch of token-level datums and accumulates its gradients. The next optimizer step applies them. The response is a future; read the loss and per-token log probabilities from GET /v1/training/jobs/{job_id}/futures/{future_id}. POST /v1/training/jobs/{job_id}/forward takes the same body and computes the loss without gradients.

Request

string
requis
Your Fastino API key.
string
requis
Interactive job ID.
object[]
requis
One or more training examples. Tokenize them yourself with the base model’s tokenizer.
string
défaut:"cross_entropy"
cross_entropy, importance_sampling, ppo, cispo, or dro.
object
Loss settings. ppo and cispo take clip_low_threshold and clip_high_threshold; dro takes beta. Unknown keys are rejected.

Response

string
The queued future.
string
The job.
string
forward_backward.

Errors

Problems found while the batch runs, such as a missing loss input, mismatched tensor lengths, an unknown loss_fn_config key, or a datum longer than the model’s limit, fail the future. Its error.category is user.