feat: Langfuse integration, system-wide tracing configuration (LangSmith&Langfuse)

[maciejmajek]

Purpose

Tracing agents is crucial for debugging, transparency, safety and more. At the moment, the code only works with LangSmith tracing (a paid solution). RAI has to provide an alternative, like LangFuse.

Proposed Changes

What does this PR add, remove or fix?

Issues

• Links to relevant issues

Testing

Setup langfuse: https://langfuse.com/docs/deployment/local
Go to http://localhost:3000, create account, organization and project.
configure langfuse tracing in config.toml

[tracing.langfuse]
use_langfuse = true
host = "http://localhost:3000"

Add the config to the main agent.invoke

from rai.utils.model_initialization import get_llm_model, get_tracing_callbacks
...
self.agent.invoke(
            {"messages": self.history}, config={"callbacks": get_tracing_callbacks()}
        )

[boczekbartek]

@maciejmajek Such a great idea to have an open-source alternative for paid services!

Please document how to use Langfuse (and LangSmith if possible). I think new users might not know that it's possible.

How about adding it to:

• tracing.md in https://github.com/RobotecAI/rai/tree/development/docs
  or
• https://github.com/RobotecAI/rai/blob/development/docs/vendors.md
  ?

[maciejmajek]

Multimodal tracing works in langsmith, langfuse has limited capability (works with links, but not with base64 images that we use yet)

[adamdbrw]

Some suggestions, rather minor

[adamdbrw]

I would always start with the open source option when reading from the top, and make the distinction extra clear, i.e.:

Langfuse (open-source)

LangSmith (closed-source, paid)

[adamdbrw]

Suggested change

	- [Tracing](tracing.md) configuration.
	- [Tracing](tracing.md) configuration for AI models.

[adamdbrw]

Important step for full open-source tool set