---
title: "Compare OEP research data with MaStR installations for a grid operator"
method: POST
path: "/api/oep/compare-mastr"
tags: ["OEP (Open Energy Platform)"]
---

# Compare OEP research data with MaStR installations for a grid operator

`POST /api/oep/compare-mastr`

## Request

- Base URL: `https://api.cernion.de`
- URL: `https://api.cernion.de/api/oep/compare-mastr`
- Auth: none declared

Loads OEP table rows and MaStR installations in parallel (Promise.allSettled) and returns a side-by-side semantic delta comparison. Graceful when OEP is offline — oep.available will be false but the MaStR data is still returned. Large requested portfolios (>5000 rows or `limit: "all"`) use the standard async job pattern for REST callers.

## Query parameters

- `token` string

## Request body

- object
  - `gridOperatorId` string, required: MaStR grid operator ID (SNB…)
  - `oepSchema` string
  - `oepTable` string
  - `installationType` 'solar' | 'wind' | 'storage' | 'biomass' | 'hydro' | 'combustion' | 'all': Installation type for MaStR query. Use "all" for an aggregated portfolio comparison.
  - `limit` union
    - integer
    - 'all'
  - `token` string: Optional Cernion MCP token for this request. Overrides CERNION_TOKEN when provided.

## Response `200`

OEP and MaStR counts with semantic delta output

- object
  - `oep` object
    - `available` boolean
    - `count` integer
    - `source` string
  - `mastr` object
    - `available` boolean
    - `count` integer
    - `source` string
  - `delta` object, nullable
    - `matchedPairs` integer
    - `mastrOnly` integer
    - `oepOnly` integer
    - `totalUnmatched` integer
    - `capacityDeltaMW` number
    - `fieldDeltas` object
    - `topMismatches` object[]
  - `oeoMappingNote` string
  - `_evidence` object[]

## Other responses

- `202`: Job accepted for large comparison request

---

[API](https://skmtc.dev/cernion/apis/cernion-energy-tools-api.md) · [All operations](https://skmtc.dev/cernion/apis/cernion-energy-tools-api/llms.txt) · [OpenAPI document](https://skmtc.dev/cernion/apis/cernion-energy-tools-api/revisions/cdb94473b538?raw)