---
title: "Read Delta"
method: POST
path: "/api/v1/datasets/{dataset_id}/runs/delta"
tags: ["datasets"]
---

# Read Delta

`POST /api/v1/datasets/{dataset_id}/runs/delta`

Fetch the number of regressions/improvements for each example in a dataset, between sessions[0] and sessions[1].

## Path parameters

- `dataset_id` string, uuid, required

## Request body

- QueryFeedbackDelta
  - `baseline_session_id` string, uuid, required
  - `comparison_session_ids` string[], required
  - `feedback_key` string, required
  - `filters` object, nullable
  - `offset` integer
  - `limit` integer
  - `comparative_experiment_id` string, uuid, nullable

## Response `200`

Successful Response

- SessionFeedbackDelta — List of feedback keys with number of improvements and regressions for each.
  - `feedback_deltas` object, required

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.net/langchain-ai/apis/langsmith.md) · [All operations](https://skmtc.net/langchain-ai/apis/langsmith/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/langchain-ai/langsmith/versions/a0acb3a6a101/schema)