curl --request POST \
  --url https://api.us.lexful.app/v1/entity_types \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'X-Account-ID: <api-key>' \
  --data '
{
  "name": "secure_project",
  "display_name": "Secure Projects",
  "description": "Project management with secure credentials and file attachments",
  "is_system": false,
  "properties": [
    {
      "name": "project_name",
      "type": "string",
      "display_name": "Project Name",
      "description": "Name of the project",
      "required": true
    },
    {
      "name": "budget",
      "type": "number",
      "display_name": "Budget",
      "description": "Project budget in dollars",
      "required": false
    },
    {
      "name": "team_size",
      "type": "integer",
      "display_name": "Team Size",
      "description": "Number of team members",
      "required": false
    },
    {
      "name": "is_active",
      "type": "boolean",
      "display_name": "Active",
      "description": "Whether project is currently active",
      "required": true
    },
    {
      "name": "milestones",
      "type": "array",
      "display_name": "Milestones",
      "description": "Project milestones and deliverables",
      "required": false,
      "array": {
        "type": "object",
        "properties": [
          {
            "name": "title",
            "type": "string",
            "display_name": "Milestone Title",
            "required": true
          },
          {
            "name": "completion_percentage",
            "type": "integer",
            "display_name": "Completion %",
            "required": true
          }
        ]
      }
    },
    {
      "name": "api_key",
      "type": "secret",
      "display_name": "API Key",
      "description": "Encrypted API key for external integration",
      "required": false
    },
    {
      "name": "mfa_token",
      "type": "totp",
      "display_name": "MFA Token",
      "description": "Time-based one-time password for authentication",
      "required": false
    },
    {
      "name": "project_plan",
      "type": "file",
      "display_name": "Project Plan",
      "description": "Project planning document",
      "required": false,
      "file_rules": {
        "max_size": 10485760,
        "allowed_extensions": [
          ".pdf",
          ".docx",
          ".xlsx"
        ],
        "allowed_mime_types": [
          "application/pdf",
          "application/vnd.openxmlformats-officedocument.wordprocessingml.document"
        ]
      }
    },
    {
      "name": "start_date",
      "type": "date",
      "display_name": "Start Date",
      "description": "Project start date",
      "required": true
    },
    {
      "name": "last_activity",
      "type": "datetime",
      "display_name": "Last Activity",
      "description": "Last activity timestamp",
      "required": false
    },
    {
      "name": "description",
      "type": "richtext",
      "display_name": "Description",
      "description": "Project description with formatting",
      "required": false
    },
    {
      "name": "detailed_specification",
      "type": "richtext_large",
      "display_name": "Detailed Specification",
      "description": "Complete project specification document",
      "required": false
    }
  ],
  "references": [
    {
      "name": "project_lead",
      "display_name": "Project Lead",
      "description": "Primary contact responsible for project",
      "required": true,
      "multiple": false,
      "target_entity_types": [
        "system.contact"
      ]
    },
    {
      "name": "team_members",
      "display_name": "Team Members",
      "description": "Project team members",
      "required": false,
      "multiple": true,
      "target_entity_types": [
        "system.contact"
      ]
    }
  ]
}
'

{
  "id": "019983a9-c4bf-77da-a35b-5eb177b7b859",
  "account_id": "019983a9-c4bf-77da-a35b-5eb177b7b859",
  "name": "system.contact",
  "display_name": "Contacts",
  "description": "Contacts are people and identities associated with an organization",
  "is_system": true,
  "properties": [
    {
      "name": "first_name",
      "type": "string",
      "display_name": "First Name",
      "required": false
    },
    {
      "name": "last_name",
      "type": "string",
      "display_name": "Last Name",
      "required": false
    },
    {
      "name": "title",
      "type": "string",
      "display_name": "Title",
      "required": false
    },
    {
      "name": "important",
      "type": "boolean",
      "display_name": "Important",
      "required": true
    },
    {
      "name": "contact_type",
      "type": "string",
      "display_name": "Contact Type",
      "required": false,
      "enum": [
        "Approver",
        "Champion",
        "Decision Maker",
        "End User",
        "Evaluator",
        "Influencer",
        "Owner",
        "Other"
      ]
    },
    {
      "name": "contact_methods",
      "type": "array",
      "display_name": "Contact Methods",
      "required": false,
      "array": {
        "type": "object",
        "properties": [
          {
            "name": "type",
            "type": "string",
            "display_name": "Contact Method Type",
            "required": true,
            "enum": [
              "Phone",
              "Fax",
              "Mobile",
              "Email",
              "Website",
              "Twitter",
              "LinkedIn",
              "Other"
            ]
          },
          {
            "name": "value",
            "type": "string",
            "display_name": "Contact Method Value",
            "required": true
          }
        ]
      }
    },
    {
      "name": "preferred_contact_method",
      "type": "string",
      "display_name": "Preferred Contact Method",
      "required": false,
      "enum": [
        "Phone",
        "Fax",
        "Mobile",
        "Email",
        "Website",
        "Twitter",
        "LinkedIn",
        "Other"
      ]
    },
    {
      "name": "notes",
      "type": "richtext",
      "display_name": "Notes",
      "required": false
    }
  ],
  "references": [
    {
      "name": "location",
      "display_name": "Location",
      "required": false,
      "multiple": false,
      "target_entity_types": [
        "system.location"
      ]
    }
  ],
  "version": 1,
  "created_at": "2024-01-15T10:30:00.000Z",
  "updated_at": "2024-01-15T10:30:00.000Z",
  "created_by": "019983a9-c4c0-73af-aec9-463feeadc2e7",
  "updated_by": "019983a9-c4c0-73af-aec9-463feeadc2e7"
}