---
title: "Custom Runtime Apply"
method: PUT
path: "/v2/{entity}/{project}/runtimes/{runtime_name}"
tags: ["Custom Runtimes"]
---

# Custom Runtime Apply

`PUT /v2/{entity}/{project}/runtimes/{runtime_name}`

## Request

- Base URL: `https://trace.wandb.ai` (the document declares no server; this is the origin it was published from)
- URL: `https://trace.wandb.ai/v2/{entity}/{project}/runtimes/{runtime_name}`
- Auth: none declared

Create or replace a custom runtime configuration.

## Path parameters

- `entity` string, required
- `project` string, required
- `runtime_name` string, required: Stable name of the custom runtime to create or replace

## Request body

- CustomRuntimeApplyBody
  - `base_url` string, required: Public OpenAI-compatible endpoint base URL
  - `api_key_secret` string, nullable: Team secret name used as the endpoint API key; never the secret value
  - `headers` object: Literal headers forwarded to the endpoint
  - `runtime_ids` CustomRuntimeID[], required: Complete desired list of IDs exposed by the endpoint
    - `id` string, required: Value sent in the OpenAI-compatible request model field
    - `max_tokens` integer: Maximum tokens supported by this runtime ID

## Response `200`

Successful Response

- CustomRuntimeApplyRes
  - `name` string, required: Stable custom runtime name
  - `base_url` string, required
  - `api_key_secret` string, nullable, required
  - `headers` object, required
  - `runtime_ids` CustomRuntimeIDRes[], required
    - `id` string, required: Value sent in the OpenAI-compatible request model field
    - `max_tokens` integer, required: Maximum tokens supported by this runtime ID
    - `playground_id` string, required

## Other responses

- `422`: Validation Error

## Changes

- **2026-10-16** `dd89fadfe4e4`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/wandb/apis/fastapi/changes/v2/:entity/:project/runtimes/:runtime_name/put.md)

---

[API](https://skmtc.dev/wandb/apis/fastapi.md) - [All operations](https://skmtc.dev/wandb/apis/fastapi/llms.txt) - [OpenAPI document](https://skmtc.dev/wandb/apis/fastapi/revisions/f7643c49bf2e?raw)