Overview

Wafer is an OpenAI-compatible provider with a dedicated Bifrost provider implementation. Bifrost uses the shared OpenAI-compatible request and response converters, while preserving Wafer-specific extra parameters. Key characteristics:

OpenAI-compatible chat - Chat Completions use /chat/completions
Streaming support - Server-Sent Events for chat and text completions
Tool calling - Function tools are passed through using the OpenAI-compatible schema
Reasoning support - Reasoning models return reasoning via reasoning_content
Responses API - Supported by converting Responses requests to Chat Completions internally
Text completions - Text completions use Wafer’s /completions endpoint
File uploads - Upload media once and reference it by file_id in chat requests

Supported Operations

Operation	Non-Streaming	Streaming	Endpoint
Chat Completions	✅	✅	`/chat/completions`
Responses API	✅	✅	`/chat/completions`
Text Completions	✅	✅	`/completions`
List Models	✅	-	`/models`
File Upload	✅	-	`/files`
Embeddings	❌	❌	-
Image Generation	❌	❌	-
Speech (TTS)	❌	❌	-
Transcriptions (STT)	❌	❌	-
Batch	❌	❌	-

Setup & Configuration

Configure Wafer as a provider.

Web UI
config.json
API
Go SDK

Navigate to Models > Model Providers. Look for Wafer under Configured Providers. If it is missing, click on Add New Provider and select Wafer.
Click Add Key or edit an existing key.
Set a name for your key.
Paste your API key directly or use an environment variable (for example, env.WAFER_API_KEY).
Set Allowed Models to All Models (default) or the specific model allowlist you want this key to serve.
To upload files, enable Use for Batch APIs on the key (this flag also gates file operations).
Save the provider configuration.

{
  "providers": {
    "wafer": {
      "keys": [
        {
          "name": "wafer-key-1",
          "value": "env.WAFER_API_KEY",
          "models": [
            "*"
          ],
          "weight": 1.0,
          "use_for_batch_api": true
        }
      ]
    }
  }
}

case schemas.Wafer:
    return []schemas.Key{{
        Name:           "wafer-key-1",
        Value:          *schemas.NewSecretVar("env.WAFER_API_KEY"),
        Models:         []string{"*"},
        Weight:         1.0,
        UseForBatchAPI: bifrost.Ptr(true),
    }}, nil

1. Chat Completions

Request Parameters

Wafer supports OpenAI-compatible chat completion parameters. For the full parameter reference and message conversion behavior, see OpenAI Chat Completions. Available chat models include glm-5.2 and kimi-k2.6.

curl -X POST http://localhost:8080/v1/chat/completions \
  -H "Content-Type: application/json" \
  -d '{
    "model": "wafer/glm-5.2",
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

Reasoning Parameter

Wafer delegates through ToOpenAIChatRequest with provider-specific compatibility handling. Reasoning models return reasoning content via reasoning_content. Assistant-message reasoning details are stripped before sending follow-up messages because Wafer rejects reasoning_details in assistant messages.

Extra Parameters

Wafer enables passthrough extra parameters for chat and text completion requests. Provider-specific options can be sent through extra_params without being dropped by Bifrost.

Wafer fails fast on unsupported parameters, returning an error rather than silently ignoring them. Bifrost filters OpenAI-specific parameters before forwarding to avoid these rejections.

2. Responses API

Bifrost converts Responses API format to Chat Completions internally, then converts the response back:

BifrostResponsesRequest
  → ToChatRequest()
  → ChatCompletion
  → ToBifrostResponsesResponse()

Same parameter support as Chat Completions with response format differences (output items instead of message content). Streaming Responses requests are also routed through Chat Completions streaming.

3. Text Completions

Wafer supports text completions through /completions:

Parameter	Mapping
`prompt`	Sent as-is
`max_tokens`	max_tokens
`temperature`	temperature
`top_p`	top_p
`stop`	stop sequences
`extra_params`	Passed through to Wafer

Response returns choices[].text with completion text. Streaming text completions use Wafer’s OpenAI-compatible SSE format on /completions.

4. List Models

Lists available models from Wafer through /models.

5. File Upload

Upload a file once and reference it by file_id in later chat requests, avoiding per-request body size limits. Wafer accepts raw file bytes with metadata in HTTP headers (not a multipart form):

Content-Type - the file’s MIME type (required; validated against the purpose)
X-Wafer-Purpose - vision, document, or video (required)
X-Wafer-Filename - optional label

Uploads go to /files and return a file_id. Files expire after 30 days.

File operations reuse the batch key filter: only keys with Use for Batch APIs enabled are eligible. Enable it on at least one Wafer key, or uploads fail with no config found for batch apis.

Referencing a file in a chat completion

Reference an uploaded image by nesting its file_id inside image_url (in place of url):

{
  "type": "image_url",
  "image_url": { "file_id": "file_8a3c4d5e6f7a8b9c0d1e2f3a4b5c6d7e" }
}

Overview

Quick Start

Release Cadence

Migration Guides

SDK Integrations

Providers & Guides

MCP Gateway

Custom plugins

Open Source Features

Wafer

Overview

Supported Operations

Setup & Configuration

1. Chat Completions

Request Parameters

Reasoning Parameter

Extra Parameters

2. Responses API

3. Text Completions

4. List Models

5. File Upload

Referencing a file in a chat completion

​Overview

​Supported Operations

​Setup & Configuration

​1. Chat Completions

​Request Parameters

​Reasoning Parameter

​Extra Parameters

​2. Responses API

​3. Text Completions

​4. List Models

​5. File Upload

​Referencing a file in a chat completion

Overview

Supported Operations

Setup & Configuration

1. Chat Completions

Request Parameters

Reasoning Parameter

Extra Parameters

2. Responses API

3. Text Completions

4. List Models

5. File Upload

Referencing a file in a chat completion