---
title: "Create Completion Sync Task"
method: POST
path: "/v1/llm/completions-sync"
---

# Create Completion Sync Task

`POST /v1/llm/completions-sync`

Runs a sync prompt completion on an LLM.

## Query parameters

- `model_endpoint_name` string, required

## Request body

- CompletionSyncV1Request — Request object for a synchronous prompt completion task.
  - `prompt` string, required
  - `max_new_tokens` integer, required
  - `temperature` number, required
  - `stop_sequences` string[], nullable
  - `return_token_log_probs` boolean, nullable
  - `presence_penalty` number, nullable
  - `frequency_penalty` number, nullable
  - `top_k` integer, nullable
  - `top_p` number, nullable
  - `include_stop_str_in_output` boolean, nullable
  - `guided_json` object, nullable
  - `guided_regex` string, nullable
  - `guided_choice` string[], nullable
  - `guided_grammar` string, nullable
  - `skip_special_tokens` boolean, nullable

## Response `200`

Successful Response

- CompletionSyncV1Response — Response object for a synchronous prompt completion.
  - `request_id` string, nullable
  - `output` CompletionOutput — Represents the output of a completion request to a model.
    - `text` string, required
    - `num_prompt_tokens` integer, nullable
    - `num_completion_tokens` integer, required
    - `tokens` TokenOutput[], nullable
      - `token` string, required
      - `log_prob` number, required

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/scaleapi/apis/launch.md) · [All operations](https://skmtc.net/scaleapi/apis/launch/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/scaleapi/launch/versions/8333576dbe43/schema)