https://github.com/ethereum/eth1.0-apis/blob/c8fa3348b7fbe42e230a094460a68adfd8403aca/src/schemas/block.json#L93-L109

this doesnt look right combining headerObject with an array of tx hashes.

it should be combining type: 'object's together with the correct shape that you want to merge:

"allOf": [
      {
        "$ref": "./Header.json#/headerObject"
      },
      {
       "type: "object",
       "properties": {
           "transactions": {
              "$ref": "./Block.json#/transactionHash"
           }
       },
        {
       "type: "object",
       "properties": {
           "uncles": {
              "$ref": "./Block.json#/transactionHash"
           }
       }
]       

the name transactionHash seems like an incorrect name for an array of transaction hashes.

also you can pass true to eth_getBlockByNumber and it returns the transactions filled out instead of just the hashes:

so it needs to take that into account too