If you run the example demo-spring-boot-3-webmvc
navigate to http://localhost:8081/v3/api-docs
you notice that:
    "/pet/findByTags": {
...
        "responses": {
...
          "200": {
...
              "application/json": {
                "schema": {
                  "type": "array", # <- this line is missing
                  "items": {
                    "$ref": "#/components/schemas/Pet"
                  }
                }
If you disable in application.yaml
springdoc:
  #api-docs:
    #version: openapi_3_1
the type isnt missing.