---
title: "Compare Backtests"
method: GET
path: "/v1/backtests/compare"
---

# Compare Backtests

`GET /v1/backtests/compare`

## Request

- Base URL: `https://api.quantradin.com` (the document declares no server; this is the origin it was published from)
- URL: `https://api.quantradin.com/v1/backtests/compare`
- Auth: none declared

Diff two of the CALLER'S OWN backtests (owner-scoped: both must belong
to the resolved user, else 404). Headline = the optimism-gap delta —
the overfitting signal, not the raw EV delta. Auth: the shared
resolver — session cookie wins, else X-Vega-Key, else a Build-10
account key pair resolved to the desk owner's user_id.

P1-F2: refused (403, friendly) for the SHARED guest key with no session —
two run_ids from the one demo tenant may belong to two different visitors,
so "your own runs" isn't a truthful claim there.

## Query parameters

- `a` string, required
- `b` string, required

## Headers

- `x-vega-key` string, nullable

## Response `200`

Successful Response

- unknown

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/quantradin/apis/vega-api.md) · [All operations](https://skmtc.dev/quantradin/apis/vega-api/llms.txt) · [OpenAPI document](https://skmtc.dev/quantradin/apis/vega-api/revisions/47add154ef38?raw)