Migration Guide from the Legacy predictions Endpoint

Retired: The native /predictions endpoint retired on May 5, 2026.

If you use the native /predictions endpoint (For example: https://inference.de-txl.ionos.com/models/{modelId}/predictions), migrate to the OpenAI-compatible API for standard text and image generation use cases. The migration does not affect the /collections, /documents, and /query endpoints.

This migration simplifies integration with OpenAI-compatible tools and SDKs and provides a standardized developer experience.

Before you begin

To complete this migration you need:

• An active IONOS AI Model Hub account with a valid API token.

• A model ID for your use case, which you can retrieve from https://openai.inference.de-txl.ionos.com/v1/models.

• An existing document collection. It is required for Retrieval Augmented Generation (RAG) only.

Best practice: Place the retrieved context in the system message to separate the instructional context from the user’s question. The approach ensures a cleaner separation of concerns, simplifies follow-up questions, and improves model adherence to grounding information.

Migrate text generation

1

Update the endpoint URL

Replace the native endpoint with the OpenAI-compatible chat completions endpoint:

• Before: POST https://inference.de-txl.ionos.com/models/{modelId}/predictions

• After: POST https://openai.inference.de-txl.ionos.com/v1/chat/completions

Note: Move the model ID from the URL to the request body. You can retrieve available IDs using https://openai.inference.de-txl.ionos.com/v1/models. Example: openai/gpt-oss-120b.

2

Restructure the request body

Before:

{
  "type": "prediction",
  "properties": {
    "input": "Please give me 5 domain suggestions for a flower shop in Berlin. Provide for each domain name a paragraph explaining the domain name and why it is valuable.",
    "options": {
      "max_length": "1000",
      "temperature": "0.5"
    }
  }
}

After:

{
  "model": "openai/gpt-oss-120b",
  "messages": [
    {
      "role": "system",
      "content": "You are a helpful assistant."
    },
    {
      "role": "user",
      "content": "Please give me 5 domain suggestions for a flower shop in Berlin. Provide for each domain name a paragraph explaining the domain name and why it is valuable."
    }
  ],
  "max_tokens": 2000,
  "temperature": 0.5
}

3

Update field names

Native field	OpenAI-compatible field
properties.input	messages[].content (user role)
properties.options.max_length	max_tokens
properties.options.temperature	temperature
modelId in the URL	model in the request body

Migrate image generation

1

Update the endpoint URL

Replace the native endpoint with the OpenAI-compatible images endpoint:

• Before: POST https://inference.de-txl.ionos.com/models/{modelId}/predictions

• After: POST https://openai.inference.de-txl.ionos.com/v1/images/generations

Note: You can retrieve available model IDs using https://openai.inference.de-txl.ionos.com/v1/models. Example: black-forest-labs/FLUX.1-schnell.

2

Restructure the request body

Before:

{
  "type": "prediction",
  "properties": {
    "input": "Draw an image of a futuristic city skyline at sunset, digital art.",
    "options": {
      "size": "1024x1024"
    }
  }
}

After:

{
  "model": "black-forest-labs/FLUX.1-schnell",
  "prompt": "A futuristic city skyline at sunset, digital art.",
  "n": 1,
  "size": "1024x1024"
}

3

Update field names

Native field	OpenAI-compatible field
properties.input	prompt
properties.options.size	size
modelId in the URL	model in the request body

Migrate retrieval augmented generation

Users requiring Retrieval-Augmented Generation (RAG) or document-based querying can now migrate to the native /query endpoint alongside the OpenAI-compatible API. This approach splits the process into two distinct steps:

1

Query your document collection

Endpoint: POST https://inference.de-txl.ionos.com/collections/{collectionId}/query

Request Body:

{
  "query": "What are the supported models for AI Model Hub?",
  "limit": 5
}

Response Example:

{
  "results": [
    {
      "documentId": "doc-123",
      "content": "IONOS AI Model Hub supports various models including GPT-OSS-120B, Llama 3, Mistral, and FLUX.1 for image generation...",
      "score": 0.92
    },
    {
      "documentId": "doc-456",
      "content": "The following embedding models are available: text-embedding-ada-002...",
      "score": 0.87
    }
  ]
}

2

Generate a response using retrieved context

Endpoint: POST https://openai.inference.de-txl.ionos.com/v1/chat/completions

Request Body:

{
  "model": "openai/gpt-oss-120b",
  "messages": [
    {
      "role": "system",
      "content": "You are a helpful assistant. Answer the user's question based only on the provided context. If the context doesn't contain enough information, say so.\n\nContext:\n---\nIONOS AI Model Hub supports various models including GPT-OSS-120B, Llama 3, Mistral, and FLUX.1 for image generation...\n\nThe following embedding models are available: text-embedding-ada-002...\n---"
    },
    {
      "role": "user",
      "content": "Which models does IONOS AI Model Hub offer?"
    }
  ],
  "max_tokens": 1000,
  "temperature": 0
}