---
title: "Create Log"
method: POST
path: "/api/v1/repos/{owner}/{repo}/optimization-jobs/{job_id}/logs"
tags: ["optimization-jobs"]
---

# Create Log

`POST /api/v1/repos/{owner}/{repo}/optimization-jobs/{job_id}/logs`

## Request

- Base URL: `https://api.smith.langchain.com`
- URL: `https://api.smith.langchain.com/api/v1/repos/{owner}/{repo}/optimization-jobs/{job_id}/logs`
- Auth: one of:
  - API key in header `X-API-Key`
  - API key in header `X-Tenant-Id`
  - HTTP bearer

Create a new log entry for a prompt optimization job.

## Path parameters

- `job_id` string, uuid, required

## Request body

- PromptOptimizationJobLogCreate
  - `log_type` 'info' | 'result' | 'error' | 'link', required
  - `message` string, required
  - `data` object, nullable

## Response `200`

Successful Response

- PromptOptimizationJobLog
  - `log_type` 'info' | 'result' | 'error' | 'link', required
  - `message` string, required
  - `data` object, nullable
  - `id` string, uuid, required
  - `job_id` string, uuid, required
  - `created_at` string, date-time, required

## Other responses

- `422`: Validation Error

## Changes

- **2026-10-16** `1a8ee9358d81`: 4 breaking
  - the `detail/items/` response's property type changed from `object` to `string` for status `422`
  - removed the required property `detail/items/loc` from the response with the `422` status
  - removed the required property `detail/items/msg` from the response with the `422` status
  - removed the required property `detail/items/type` from the response with the `422` status

[Operation history](https://skmtc.dev/langchain-ai/apis/langsmith/changes/api/v1/repos/:owner/:repo/optimization-jobs/:job_id/logs/post.md)

---

[API](https://skmtc.dev/langchain-ai/apis/langsmith.md) - [All operations](https://skmtc.dev/langchain-ai/apis/langsmith/llms.txt) - [OpenAPI document](https://skmtc.dev/langchain-ai/apis/langsmith/revisions/7a01c01f75e8?raw)