---
title: "GET /experimental/eval-run-comparisons"
method: GET
path: "/experimental/eval-run-comparisons"
tags: ["Evals"]
---

# GET /experimental/eval-run-comparisons

`GET /experimental/eval-run-comparisons`

Returns side-by-side stats for 2-10 eval runs over the same scenarios. Scenarios linked to every run are grouped and labeled with the dimensions that vary (e.g. model). Scenarios linked to only some runs are listed as uncomparable. Responds 400 when fewer than 2 or more than 10 distinct run IDs are given.

## Query parameters

- `runs` union, required
  - string, uuid
  - string[]

## Response `200`

Default Response

- object
  - `links` object, required
    - `self` string, uri, required
  - `data` object, required
    - `id` 'comparison', required
    - `type` 'eval-run-comparison', required
    - `attributes` object, required
      - `runs` object[], required
        - `id` string, uuid, required
        - `metadata` unknown, required
        - `variedDimensions` object, required
      - `variedDimensionKeys` string[], required
      - `comparable` object[], required
        - `scenarioFingerprint` string, required
        - `groups` object[], required
          - `variant` string, required
          - `runs` object[], required
            - `runId` string, uuid, required
            - `stats` object, required
              - …
      - `uncomparable` object[], required
        - `scenarioFingerprint` string, required
        - `presentInRunIds` string[], required

## Other responses

- `400` — Bad Request
- `404` — Not Found
- `500` — Internal Server Error

## Changes

- **2026-09-02** `d18817d8161c` — 1 info
  - endpoint added

[Change history](https://skmtc.dev/tessl/apis/tessl-api/changes/experimental/eval-run-comparisons/get.md)

---

[API](https://skmtc.dev/tessl/apis/tessl-api.md) · [All operations](https://skmtc.dev/tessl/apis/tessl-api/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/tessl/tessl-api/revisions/d18817d8161c/schema)