---
title: "POST /compatibility/subjects/{subject}/versions/{version}"
method: POST
path: "/compatibility/subjects/{subject}/versions/{version}"
tags: ["Compatibility"]
---

# POST /compatibility/subjects/{subject}/versions/{version}

`POST /compatibility/subjects/{subject}/versions/{version}`

## Request

- The document declares no server URL.
- Auth: none declared

## Path parameters

- `subject` string, required
- `version` string, required

## Query parameters

- `verbose` boolean
- `normalize` boolean

## Headers

- `X-Registry-GroupId` string

## Request body

- RegisterSchemaRequest
  - `schema` string, required: The schema definition as a string.
  - `schemaType` string: The schema format (AVRO, PROTOBUF, JSON). Default is AVRO.
  - `references` SchemaReference[]: A list of referenced schemas.
    - `name` string, required
    - `subject` string, required
    - `version` integer, required
  - `metadata` object: Optional metadata associated with the schema.
  - `ruleSet` object: Optional ruleset configuration for the schema.

## Response `200`

Compatibility check result.

- CompatibilityCheckResponse
  - `is_compatible` boolean, required: True if the schema is compatible, false otherwise.
  - `messages` string[]: Error messages explaining compatibility violations (only present when verbose=true).

## Other responses

- `404`: Error returned by the Schema Registry API
- `422`: Error returned by the Schema Registry API
- `500`: Error returned by the Schema Registry API

## Changes

- **2026-10-30** (v8) `a2f9ca447c9b`: 3 info
  - added the optional property `messages` to the response with the `200` status (media type: application/json)
  - added the optional property `messages` to the response with the `200` status (media type: application/vnd.schemaregistry.v1+json)
  - added the optional property `messages` to the response with the `200` status (media type: application/vnd.schemaregistry+json)

[Operation history](https://skmtc.dev/apicurio/apis/apicurio-registry-confluent-compatibility-api/changes/compatibility/subjects/:subject/versions/:version/post.md)

---

[API](https://skmtc.dev/apicurio/apis/apicurio-registry-confluent-compatibility-api.md) - [All operations](https://skmtc.dev/apicurio/apis/apicurio-registry-confluent-compatibility-api/llms.txt) - [OpenAPI document](https://skmtc.dev/apicurio/apis/apicurio-registry-confluent-compatibility-api/revisions/a2f9ca447c9b?raw)