init_llm(...) does not work in 7.2.0

[zhaoyang868686]

Checklist

• My issue is not an AI Core service issue, but an SDK issue.
• My issue is a Python related issue, not a JS/TS or Java related issue.
• My issue is not already reported or documented.

Describe the Bug

https://help.sap.com/doc/generative-ai-hub-sdk/CLOUD/en-US/_reference/gen_ai_hub.html#harmonized-model-initialization

It seems that init_llm(...) works as expected with Python SDK 6.10.0, but no longer works with 7.2.0.

Steps to Reproduce

1. Setup Python SDK 7.2.0
2. Try init_llm(...) with this example.
3. An error occurred while initializing the LLM: 'NoneType' object has no attribute 'deployment_class'.

Expected Behavior

An error occurred while initializing the LLM: 'NoneType' object has no attribute 'deployment_class'.

Screenshots

No response

Used Versions

Python SDK 7.2.0

Code Examples

No response

Log File

No response

Region

Not listed above

Affected Development Phase

Development

Impact

No Impact

Timeline

No response

Additional Context

No response

[yamaceay]

Good point, the docs are wrong. Also mentioned here SAP/ai-sdk-python-backlog#7, quoting here:

LangchainIntegration.HarmonizedModelInitialization[0]: In the underlying subclass call, proxy client is forwarded as None, so that we run into the error NoneType has no such XXX attribute / property. For this, we should always instantiate proxy client using gen_ai_hub.proxy.core.get_proxy_client(), and maybe, it makes more sense to switch to a cheaper and more reliable model, e.g., gpt-4o, since I received empty string as a response of calling with gpt-5-nano.

So the fix to the docs is to add from gen_ai_hub.proxy.core import get_proxy_client; proxy_client=get_proxy_client('gen-ai-hub'); init_llm(..., proxy_client=proxy_client, ...)

[zhaoyang868686]

init_llm(..., proxy_client=proxy_client, ...)

In version 6.10.0, init_llm() could be called without any arguments.

This is an incompatible change from the user's perspective, as existing code that worked with 6.10.0 may no longer work after upgrading to 7.2.0.

We should explicitly mention this change in the release notes so users understand why their existing code may stop working after the upgrade and know how to update it.

[yamaceay]

Linking the current PR: #125

The PR is closed. The open PR is: #130