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[MLOB-7510] added session-level eval documentation#36958

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May 29, 2026
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[MLOB-7510] added session-level eval documentation#36958
jennm merged 17 commits into
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jenn/MLOB-7510

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@jennm jennm commented May 22, 2026

What does this PR do? What is the motivation?

This PR adds documentation of session level evals

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@github-actions github-actions Bot added the Architecture Everything related to the Doc backend label May 22, 2026
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github-actions Bot commented May 22, 2026

@github-actions github-actions Bot added the Images Images are added/removed with this PR label May 22, 2026
@jennm jennm marked this pull request as ready for review May 26, 2026 15:53
@jennm jennm requested a review from a team as a code owner May 26, 2026 15:53
@jeff-morgan-dd jeff-morgan-dd self-assigned this May 26, 2026
@jeff-morgan-dd jeff-morgan-dd added the editorial review Waiting on a more in-depth review label May 26, 2026
@jeff-morgan-dd jeff-morgan-dd removed their assignment May 26, 2026
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Created DOCS-14508 for editorial review.

jennm and others added 4 commits May 28, 2026 12:11
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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cswatt commented May 28, 2026

Pushed some formatting changes, as well as a significant amount of section reorganization, most notably:

  • Moved "Configure a session-level evaluation" to the top. A lot of users do not need to be convinced to use this feature (perhaps they already have been convinced) and are coming to this page with the express purpose of finding out how to use it. This information needs to be above-the-fold. We cannot be making any sales argument in the documentation.
  • Removed "why session-level evaluations are needed": Contained marketing language, redundant information. Just the table is sufficient to make the point that this section was intended to make, so I preserved that and moved it to "Choosing the right scope" (renamed from "When to use session scope over trace or span scope")
  • Removed "What session-level evaluations are most useful for": More of convincing users to use this feature (nice to briefly mention in documentation, but really shouldn't be much of a focus)

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Please review the changes I've made, since the structure of the page has been significantly altered. If you absolutely need to add back any of the justification material I've removed, we can discuss!

Also noted a seeming discrepancy in the configuration instructions

@jennm jennm merged commit 3fd78cf into master May 29, 2026
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@jennm jennm deleted the jenn/MLOB-7510 branch May 29, 2026 10:53
text: "Tracking user sessions"
---

A session-level evaluation runs once per [user session][9], with every trace—and every span in those traces—available to the LLM judge in a single prompt. Sessions group related interactions under a shared `session_id` (for example, a chat conversation) and can include multiple traces over an extended interaction.
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he opening leads with mechanics ("runs once per user session") before the reader knows what the feature does for them.

Suggestion - something like
A session-level evaluation runs a custom LLM-as-a-judge across an entire [user session],
every trace, and every span in those traces, in a single prompt. Use it to score things that
only make sense across a whole interaction: whether the user's goal was met, whether the
assistant stayed coherent across turns, or whether a user grew frustrated over time.

Sessions group related interactions under a shared session_id (for example, a chat
conversation) and can span multiple traces. Session scope sees context that trace- and
span-level judges cannot, because those judges only see a single request or span.


{{< img src="llm_observability/evaluations/session_level_evaluation_scope.png" alt="The Evaluate On scope picker with Session selected." style="width:100%;" >}}

<div class="alert alert-info">A session is considered complete after 30 minutes of inactivity (no new spans for that session, measured from the most recent span), at which point the evaluation runs. Spans that arrive more than 30 minutes after the previous span are not included in the evaluation.</div>
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We dont need this, there is a whole section for it.


1. Pick a sample session from the panel on the right. The pane lists the traces in that session, with the fields referenced by your prompt highlighted.

{{< img src="llm_observability/evaluations/session_level_sample_session.png" alt="The configuration page in session scope, with the sample session pane on the right showing traces and highlighted span fields." style="width:100%;" >}}
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suggest to remove. The image below is enough


{{< img src="llm_observability/evaluations/session_level_sample_session.png" alt="The configuration page in session scope, with the sample session pane on the right showing traces and highlighted span fields." style="width:100%;" >}}

Clicking on a session then lists the traces in that session, with the fields referenced by your prompt highlighted.
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Suggest to remove this text.

@rashel-ddog
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Also -

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