Null

{
  "type": "object",
  "properties": {
    "middle_name": { "type": "null" },
    "deprecated_field": { "type": "null" }
  },
  "required": ["middle_name", "deprecated_field"],
  "additionalProperties": false
}

from pydantic import BaseModel, ConfigDict

class Payload(BaseModel):
    model_config = ConfigDict(extra="forbid")

    middle_name: None
    deprecated_field: None

import { z } from "zod";

const payloadSchema = z
  .object({
    middle_name: z.null(),
    deprecated_field: z.null(),
  })
  .strict();

{
  "type": "object",
  "properties": {
    "value": {
      "anyOf": [
        { "type": "string" },
        { "type": "null" }
      ]
    }
  },
  "required": ["value"],
  "additionalProperties": false
}

from pydantic import BaseModel, ConfigDict

class Payload(BaseModel):
    model_config = ConfigDict(extra="forbid")

    value: str | None

import { z } from "zod";

const payloadSchema = z
  .object({
    value: z.string().nullable(),
  })
  .strict();