United States Postal Service · Schema

Slot Availability

Request object for checking on slot availability

GovernmentPostal ServiceShippingLogisticsAddress ValidationPackage Tracking

Properties

Name Type Description
oneTimeAppt boolean Determine query path for the search. Either oneTimeAppt or recurringAppt must be set to true.
recurringAppt boolean Determine query path for the search. Either oneTimeAppt or recurringAppt must be set to true.
mailClass string 1 FIRST CLASS MAIL, 2 PERIODICALS, 3 USPS MARKETING MAIL (PREVIOUSLY STANDARD MAIL), 4 PACKAGE SERVICES, 6 PARCEL SELECT, 7 PRIORITY MAIL
dropshipKey string The dropship key for the appointment.
appointmentType string The type of appointment. PALLET = 1, BEDLOAD = 2, DROP_AND_PICK = 3, SPEEDLINE = 4
appointmentStartDate string The start date of the date range of the query. Cannot be in the past. Required for recurring appointments.
appointmentEndDate string The end date of the date range of the query. Maximum of 21 days in the future. Required for recurring appointments.
destinationEntry string Dropship is YES. Origin Entry is NO.
applyTiers string The applyTiers used for the search. YES or NO
perishableInd boolean Is it perishable
userCRID string CRID of the user
schedulerID string Unique ID for mailer scheduler
schedulerCorpID string Unique ID of the corporation generated by PostalOne!
schedulerCRID string CRID assigned to Scheduler of FAST Appointment
consigneeFacility object Consignee Facility details.
detailInfo object Details of the appointment for the availability request.
preferredAppt string Preferred appointment if on one time appt selection path
apptTime string Appointment time if on recurring appt selection path
dayFrequency string Appointment daily frequency if on recurring appt selection path
weekFrequency string Appointment weekly frequency if on recurring appt selection path
apptTrackingID string ShipperApptRequestID in xml, CustomerSequenceId on one time and recurring selection paths
comments string Comments if on recurring appt selection path
schedulerContentID string value set in recurring appt selection path
shipperApptRequestID string value set in recurring appt selection path
shipperMultiStopID string value set in one time appt selection path
trailerInfo object Information about the trailer for the appointment.
View JSON Schema on GitHub

JSON Schema

usps-slot-availability-schema.json Raw ↑ 
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://artifacts.apis.io/usps/json-schema/usps-slot-availability-schema.json",
  "title": "Slot Availability",
  "description": "Request object for checking on slot availability",
  "x-generated": "2026-11-11",
  "x-method": "derived",
  "x-generator": "derive-json-schema.py",
  "x-source": "openapi/usps-appointments-openapi.yml#/components/schemas/SlotAvailability",
  "type": "object",
  "required": [
    "mailClass",
    "dropshipKey",
    "destinationEntry",
    "detailInfo",
    "consigneeFacility"
  ],
  "properties": {
    "oneTimeAppt": {
      "type": "boolean",
      "description": "Determine query path for the search.\n\nEither oneTimeAppt or recurringAppt must be set to true.\n"
    },
    "recurringAppt": {
      "type": "boolean",
      "description": "Determine query path for the search.\n\nEither oneTimeAppt or recurringAppt must be set to true.\n"
    },
    "mailClass": {
      "description": "1 FIRST CLASS MAIL, 2 PERIODICALS, 3 USPS MARKETING MAIL (PREVIOUSLY STANDARD MAIL), 4 PACKAGE SERVICES, 6 PARCEL SELECT, 7 PRIORITY MAIL",
      "type": "string",
      "enum": [
        "FIRST_CLASS",
        "PERIODICALS",
        "USPS_MARKETING_MAIL",
        "PACKAGE_SERVICES",
        "PARCEL_SELECT",
        "PRIORITY_MAIL"
      ]
    },
    "dropshipKey": {
      "pattern": "^[A-Za-z0-9]{7}$",
      "type": "string",
      "description": "The dropship key for the appointment.",
      "minLength": 7,
      "maxLength": 7
    },
    "appointmentType": {
      "type": "string",
      "description": "The type of appointment. PALLET = 1, BEDLOAD = 2, DROP_AND_PICK = 3, SPEEDLINE = 4",
      "enum": [
        "PALLET",
        "BEDLOAD",
        "DROP_AND_PICK",
        "SPEEDLINE"
      ]
    },
    "appointmentStartDate": {
      "type": "string",
      "description": "The start date of the date range of the query. Cannot be in the past.\n\nRequired for recurring appointments.\n",
      "format": "date-time"
    },
    "appointmentEndDate": {
      "type": "string",
      "description": "The end date of the date range of the query.  Maximum of 21 days in the future.\n\nRequired for recurring appointments.\n",
      "format": "date-time"
    },
    "destinationEntry": {
      "description": "Dropship is YES. Origin Entry is NO.",
      "type": "string",
      "enum": [
        "YES",
        "NO"
      ]
    },
    "applyTiers": {
      "description": "The applyTiers used for the search. YES or NO",
      "type": "string",
      "enum": [
        "YES",
        "NO"
      ]
    },
    "perishableInd": {
      "type": "boolean",
      "description": "Is it perishable"
    },
    "userCRID": {
      "pattern": "^[0-9]{2,18}$",
      "type": "string",
      "description": "CRID of the user",
      "minLength": 2,
      "maxLength": 18
    },
    "schedulerID": {
      "pattern": "^[A-Za-z0-9]{1,12}$",
      "description": "Unique ID for mailer scheduler",
      "type": "string",
      "minLength": 1,
      "maxLength": 12
    },
    "schedulerCorpID": {
      "pattern": "^[A-Za-z0-9]{1,12}$",
      "description": "Unique ID of the corporation generated by PostalOne!",
      "type": "string",
      "minLength": 1,
      "maxLength": 12
    },
    "schedulerCRID": {
      "pattern": "^[0-9]{2,15}$",
      "description": "CRID assigned to Scheduler of FAST Appointment",
      "type": "string",
      "minLength": 2,
      "maxLength": 15
    },
    "consigneeFacility": {
      "description": "Consignee Facility details.",
      "type": "object",
      "properties": {
        "facilityNumber": {
          "pattern": "^[A-Za-z0-9]{1,15}$",
          "description": "Facility number",
          "type": "string",
          "minLength": 1,
          "maxLength": 15
        },
        "facilityType": {
          "pattern": "^[A-Za-z0-9]{1,15}$",
          "description": "Type of facility",
          "type": "string",
          "minLength": 1,
          "maxLength": 15
        }
      }
    },
    "detailInfo": {
      "description": "Details of the appointment for the availability request.",
      "type": "object",
      "properties": {
        "consigneeContainerGroupingID": {
          "description": "Consigner Container Grouping ID",
          "type": "string"
        },
        "shipperContainerGroupingID": {
          "description": "Shipper Container Grouping ID",
          "type": "string"
        },
        "uspsSummary": {
          "description": "Additional details of the Appointment.",
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "destinationDiscountIndicator": {
                "description": "Indicator whether this is dropship (NO) or origin entry (YES) appointment",
                "type": "string",
                "enum": [
                  "YES",
                  "NO"
                ]
              },
              "zoneSkippingIndicator": {
                "description": "Zone Skip in the Content of the appointment",
                "type": "string",
                "enum": [
                  "YES",
                  "NO"
                ]
              },
              "processingCategory": {
                "description": "Mail shape category",
                "type": "string",
                "enum": [
                  "LT",
                  "FL",
                  "CD",
                  "OS",
                  "MP",
                  "IR",
                  "PF",
                  "CM",
                  "SP",
                  "MB"
                ]
              },
              "newsIndicator": {
                "description": "Indicator for Newspaper",
                "type": "string",
                "enum": [
                  "YES",
                  "NO"
                ]
              },
              "priorityMailIndicator": {
                "description": "Priority Mail Indicator",
                "type": "string",
                "enum": [
                  "YES",
                  "NO"
                ]
              },
              "verificationLocation": {
                "description": "Verified Location for BMEU or DMU for FAST appointment",
                "type": "string",
                "enum": [
                  "BMEU",
                  "DMU"
                ]
              },
              "perishable": {
                "description": "Is it perishable.",
                "type": "string",
                "enum": [
                  "YES",
                  "NO"
                ]
              },
              "mailClass": {
                "description": "Numbers represent the mailClass within legacy systems for understanding\n\n1 FIRST CLASS MAIL\n2 PERIODICALS\n3 USPS MARKETING MAIL (PREVIOUSLY STANDARD MAIL)\n4 PACKAGE SERVICES\n6 PARCEL SELECT\n7 PRIORITY MAIL\n",
                "type": "string",
                "enum": [
                  "FIRST_CLASS",
                  "PERIODICALS",
                  "USPS_MARKETING_MAIL",
                  "PACKAGE_SERVICES",
                  "PARCEL_SELECT",
                  "PRIORITY_MAIL",
                  "USPS_GROUND_ADVANTAGE"
                ]
              },
              "rateType": {
                "description": "Rate type describes mail class and mail shape combination",
                "type": "string",
                "enum": [
                  "R",
                  "L",
                  "B",
                  "C",
                  "S",
                  "S1",
                  "S2",
                  "S3",
                  "S4",
                  "S5",
                  "S6",
                  "S7",
                  "F",
                  "A",
                  "N",
                  "P",
                  "T",
                  "D",
                  "X",
                  "H",
                  "M",
                  "Z",
                  "E",
                  "E4",
                  "G",
                  "1",
                  "2",
                  "3",
                  "4",
                  "J",
                  "K",
                  "V",
                  "W",
                  "Y",
                  "Q"
                ]
              }
            }
          }
        }
      }
    },
    "preferredAppt": {
      "description": "Preferred appointment if on one time appt selection path",
      "type": "string",
      "format": "date-time",
      "minLength": 0,
      "maxLength": 20
    },
    "apptTime": {
      "pattern": "^([01]?[0-9]|2[0-3]):[0-5][0-9]$",
      "description": "Appointment time if on recurring appt selection path",
      "type": "string",
      "minLength": 0,
      "maxLength": 5
    },
    "dayFrequency": {
      "description": "Appointment daily frequency if on recurring appt selection path",
      "type": "string",
      "enum": [
        "DAILY",
        "SATURDAY",
        "SUNDAY",
        "MONDAY",
        "TUESDAY",
        "WEDNESDAY",
        "THURSDAY",
        "FRIDAY"
      ]
    },
    "weekFrequency": {
      "description": "Appointment weekly frequency if on recurring appt selection path",
      "type": "string",
      "enum": [
        "WEEKLY",
        "BI_WEEKLY",
        "FIRST",
        "SECOND",
        "THIRD",
        "FOURTH",
        "FIFTH",
        "SIXTH"
      ]
    },
    "apptTrackingID": {
      "description": "ShipperApptRequestID in xml, CustomerSequenceId on one time and recurring selection paths",
      "type": "string",
      "minLength": 0,
      "maxLength": 30
    },
    "comments": {
      "description": "Comments if on recurring appt selection path",
      "type": "string",
      "minLength": 0,
      "maxLength": 100,
      "pattern": "^[A-Za-z0-9\\.\\-\\&\\# ]{1,100}$"
    },
    "schedulerContentID": {
      "description": "value set in recurring appt selection path",
      "type": "string",
      "minLength": 0,
      "maxLength": 30
    },
    "shipperApptRequestID": {
      "description": "value set in recurring appt selection path",
      "type": "string",
      "minLength": 0,
      "maxLength": 30
    },
    "shipperMultiStopID": {
      "description": "value set in one time appt selection path",
      "type": "string",
      "minLength": 0,
      "maxLength": 30
    },
    "trailerInfo": {
      "description": "Information about the trailer for the appointment.",
      "type": "object",
      "maxItems": 2,
      "properties": {
        "trailer": {
          "description": "max of two objects in the array",
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "trailerNumber": {
                "description": "Trailer Identifier",
                "type": "string",
                "minLength": 1,
                "maxLength": 12
              },
              "trailerLength": {
                "description": "Length of the trailer",
                "type": "string",
                "enum": [
                  "20FT",
                  "40FT",
                  "45FT",
                  "48FT",
                  "53FT"
                ]
              }
            }
          }
        },
        "carrier": {
          "description": "Details about the carrier for the appointment.",
          "type": "object",
          "properties": {
            "carrierName": {
              "description": "Name of the carrier",
              "type": "string",
              "minLength": 1,
              "maxLength": 40
            },
            "carrierCRID": {
              "description": "CRID of the carrier",
              "type": "string",
              "minLength": 2,
              "maxLength": 15
            },
            "commonContact": {
              "description": "Contact details of the appointment requestor.",
              "type": "array",
              "items": {
                "type": "object",
                "properties": {
                  "contactName": {
                    "description": "Contact name",
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 60
                  },
                  "telephone": {
                    "description": "Phone number of contact, numbers only, no delimeters, optional + sign",
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 25,
                    "pattern": "^\\+?[1-9][0-9]{7,14}$"
                  },
                  "mobilePhone": {
                    "description": "Cell phone number of contact, numbers only, no delimeters, optional + sign",
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 25,
                    "pattern": "^\\+?[1-9][0-9]{7,14}$"
                  },
                  "email": {
                    "description": "Email address of contact",
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 50,
                    "pattern": "^[a-zA-Z0-9_+&*-]+(?:\\.[a-zA-Z0-9_+&*-]+)*@(?:[a-zA-Z0-9-]+\\.)+[a-zA-Z]{2,}$"
                  },
                  "fax": {
                    "description": "Fax number of the contact, numbers only, no delimeters, optional +",
                    "type": "string",
                    "minLength": 1,
                    "maxLength": 25,
                    "pattern": "^\\+?[1-9][0-9]{7,14}$"
                  },
                  "contactID": {
                    "description": "Identification details for the appointment requestor.",
                    "type": "object",
                    "properties": {
                      "idValue": {
                        "description": "Number on ID",
                        "type": "string",
                        "minLength": 1,
                        "maxLength": 30
                      },
                      "idValueType": {
                        "description": "Type of ID used",
                        "type": "string",
                        "enum": [
                          "DRIVERS_LICENSE",
                          "EMPLOYEE_ID"
                        ]
                      }
                    }
                  },
                  "contactType": {
                    "description": "Carrier contact type",
                    "type": "string",
                    "enum": [
                      "ACCOUNT_MANAGER",
                      "CARRIER",
                      "CROSS_DOCK",
                      "CUSTOMER_SERVICE",
                      "HELP_DESK",
                      "DROP_SHIP_COORDINATOR",
                      "APPT_COORDINATOR",
                      "PLANT",
                      "INBOUND_FREIGHT_COORDINATOR",
                      "SALES_OFFICE",
                      "TRUCK_DRIVER",
                      "WAREHOUSE",
                      "OTHER"
                    ]
                  }
                }
              }
            }
          }
        },
        "billOfLadingNumberArray": {
          "description": "max of two objects in the array",
          "type": "array",
          "maxItems": 2,
          "items": {
            "type": "object",
            "properties": {
              "billOfLadingNumber": {
                "description": "Bill of lading number.",
                "type": "string",
                "minLength": 1,
                "maxLength": 15
              }
            }
          }
        }
      }
    }
  }
}

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