Add ground truth

Attach human-scored reference rows so an eval calibrates against real examples

Ground truth is a dataset of human-scored reference rows an eval retrieves from at run time, injecting the most similar ones into the evaluator prompt as calibration examples. This guide attaches a reference dataset to an existing eval, maps its columns, and turns retrieval on.

Open the Evals tab

In the left sidebar under Build, click Evals to open the Evaluations list. You can filter by use case with the tag chips, or reshape the table with Filter and Columns.

The Evaluations list under the Evals tab, showing system evals like toxicity, dead_air_detection, and conversation_hallucination with their Type, Eval Type, and Output Type columns

The Evals tab lists every evaluation in your workspace

Search for the eval

Type into the Search box to narrow the list, then pick the eval you want to add ground truth to. Here we search customer and select customer_agent_human_escalation, a Single, Agent, Pass/fail eval.

The Evaluations list filtered to customer, showing customer_agent_* evals, with a callout to select the eval you want to provide ground truth for

Search for the eval, then open it

Switch to the Ground Truth tab

On the eval’s detail page, the tab bar shows Eval Details, Usage, Feedback, and Ground Truth. Click Ground Truth. The detail page also shows the eval’s instructions and its fixed Output Type (here Pass/fail).

The customer_agent_human_escalation eval detail page with Instructions and an Output Type of Pass/fail, and a callout pointing to the Ground Truth tab

Open the Ground Truth tab from the eval’s detail page

Start from the empty state

A fresh eval has no ground truth attached. The tab reads Add ground truth dataset with the note “Upload annotated data to calibrate evaluations with human-scored reference examples.” Click anywhere in this area to open the upload drawer.

The empty Ground Truth tab reading Add ground truth dataset, with the subtext about uploading annotated data and Click anywhere to upload

Click anywhere in the empty state to begin

Choose a source in the Add Ground Truth drawer

The Add Ground Truth drawer opens on step 1, Choose Source. Drop a file into Choose a file or drag & drop (CSV, Excel .xls or .xlsx, or JSON, up to 50 MB) or use Browse files. You can also pick Choose from existing dataset to reuse a dataset you already uploaded.

The Add Ground Truth drawer on the Choose Source step, with a Browse files dropzone accepting CSV, Excel, or JSON up to 50 MB, and a Choose from existing dataset option below

Upload a file, or reuse an existing dataset

Map the input variable and upload

On step 2, Map Variables, name the ground truth set and map each eval template variable to a detected column. Columns are detected automatically; map the conversation variable to a column such as recording_url, then click Upload.

The Configure Dataset step mapping the conversation variable to the recording_url column, with the detected columns listed and an Upload button at the bottom

Map the template variable to a column, then click Upload

Configure the reference output and save

The dataset loads with a Pending status chip and a Data Preview on the right. Three settings to check:

  • Output column (required): the column that holds the expected answer; its values must match the eval’s output type, here interested_in_booking
  • Explanation (optional): a column that explains each answer, here performance_feedback
  • Examples shown, under Retrieval: how many similar rows attach to each run

Turn on Use ground truth so retrieved examples are injected into the evaluator prompt, then click Save to start generating embeddings. The top-right icons re-upload or delete the current table.

The Ground Truth tab with Use ground truth toggled on, Output column set to interested_in_booking, Explanation set to performance_feedback, and a Save button

The Output column is required and must match the eval’s output type, then Save to kick off embedding

Wait for embeddings to finish

Saving generates embeddings for the dataset in the background, shown by an Embedding… chip with a progress bar on the dataset row. Once it completes, every eval run retrieves the most similar rows and injects them into the evaluator prompt as calibration examples.

The Ground Truth tab showing an Embedding progress bar on the dataset row while embeddings generate in the background

Embedding runs in the background, the eval is ready once it finishes

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