Allow feedback submission without requiring .create() completion call (manual session/session_id registration)

[ccocks]

Currently, the Not Diamond SDK requires calling client.chat.completions.create() to generate a session_id before submitting feedback via metric.feedback(). This tightly couples feedback submission to completion generation through the SDK or API.

In many real-world use cases, users may already have completions generated externally (e.g., from self-hosted models, other APIs, or offline inference) and want to:

Submit feedback on those completions

Use Not Diamond’s routing and feedback learning without invoking .create() or re-generating completions

Avoid wasting compute/time by duplicating requests just to get session IDs

Current limitation:
Feedback submission requires a valid session_id, which currently can only be obtained by calling .create(). There is no public API or SDK method to:

Manually register a session (session ID + model/provider info)

Submit feedback linked to that manually registered session

Proposed solution:
Add support for:

A new SDK/API method to manually create/register sessions with arbitrary metadata, allowing users to associate existing completions with sessions.

Allow submitting feedback referencing these manually registered sessions without calling .create().

Possibly support a “dry-run” or “session-only” mode in .create() that skips actual generation but returns a valid session ID.

Benefits:

Enables users to integrate Not Diamond feedback with completions generated outside the SDK/API.

Avoids duplicate generation calls and wasted compute.

Makes Not Diamond routing usable in more diverse real-world scenarios (self-hosted, batch-generated, multi-cloud, etc.).

Example use case:
I have a custom LLM inference pipeline outside Not Diamond. I want to use ND’s routing feedback system without re-generating completions. Currently, I have to call .create() anyway to get a session ID, which causes wasted calls and costs.

Additional context:
Code inspection shows that metric.feedback() requires a session_id obtained only from .create(). There is no public API to register a session independently.

Thank you!