---
title: "Create run for an experiment"
method: POST
path: "/v1/experiments/{experiment_id}/runs"
tags: ["experiments"]
---

# Create run for an experiment

`POST /v1/experiments/{experiment_id}/runs`

## Path parameters

- `experiment_id` string, required

## Request body

- CreateExperimentRunRequestBody
  - `dataset_example_id` string, required — The ID of the dataset example used in the experiment run
  - `output` unknown, required
  - `repetition_number` integer, required — The repetition number of the experiment run
  - `start_time` string, date-time, required — The start time of the experiment run
  - `end_time` string, date-time, required — The end time of the experiment run
  - `trace_id` string, nullable — The ID of the corresponding trace (if one exists)
  - `error` string, nullable — Optional error message if the experiment run encountered an error

## Response `200`

Experiment run created successfully

- CreateExperimentRunResponseBody
  - `data` CreateExperimentRunResponseBodyData, required
    - `id` string, required — The ID of the newly created experiment run

## Other responses

- `403` — Forbidden
- `404` — Experiment or dataset example not found
- `409` — Experiment run already exists with a successful result and cannot be updated
- `422` — Validation Error

---

[API](https://skmtc.net/arize-ai/apis/arize-phoenix-rest-api.md) · [All operations](https://skmtc.net/arize-ai/apis/arize-phoenix-rest-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/arize-ai/arize-phoenix-rest-api/versions/a14d8ad6f708/schema)