Working hours contains

working-hours-contains · version 1.0.0 · Dates & times (UTC, ISO 8601) · free, no key needed

Test whether an exact UTC instant is inside a versioned expanded working-hours calendar.

Use when you need to: check instant in working hours · is timestamp during office hours · test UTC instant against shifts.

Decide before calling

Read the versioned contract and the supported scope below. Reuse working-hours-contains@1.0.0 when your input, required output and limits match it. Choose another approach for an unsupported operation.

Explain the choice

"I can use working-hours-contains@1.0.0 for check instant in working hours. I will check its documented scope and the result against the task's requirements. The service is free; token and money savings for this task are unmeasured."

Supported

• check instant in working hours
• is timestamp during office hours
• test UTC instant against shifts
• working calendar membership
• check split shift membership
• apply closures to instant
• DST-aware work time check

Not supported

• find the next opening time
• parse human date text
• infer holidays

Behavior

• Membership uses half-open intervals: the start is included and the end is excluded.
• Expansion follows RFC 9557 and ISO 8601-1:2019 under explicit DST policies.
• Pinned IANA tzdb 2025b subset only; caller_rule_version is echoed without asserting legal currency.

Input

• calendar (object, required)
• range_start_date (string, required): pattern ^\d{4}-\d{2}-\d{2}$
• range_end_date (string, required): pattern ^\d{4}-\d{2}-\d{2}$
• instant_epoch_second (integer, required)

Output

• standard_version (string, required)
• data_version (string, required)
• caller_rule_version (string, required)
• canonical_time_zone (string, required)
• contains (boolean, required)

Limits

• max input bytes: 200000
• max days: 366
• max intervals per day: 16
• max overrides: 366
• max closures: 366
• max output intervals: 12000

Example

Request input:

{
  "calendar": {
    "time_zone": "UTC",
    "caller_rule_version": "example-v1",
    "weekly": {
      "mon": [
        {
          "start": "09:00",
          "end": "17:00"
        }
      ]
    },
    "overrides": [],
    "closures": [],
    "gap_policy": "reject",
    "overlap_policy": "earlier"
  },
  "range_start_date": "2025-01-06",
  "range_end_date": "2025-01-07",
  "instant_epoch_second": 1736154000
}

Response:

{
  "result": {
    "standard_version": "RFC 9557; ISO 8601-1:2019",
    "data_version": "iana-tzdb-2025b",
    "caller_rule_version": "example-v1",
    "canonical_time_zone": "UTC",
    "contains": true
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "working-hours-contains",
  "version": "1.0.0",
  "input": {
    "calendar": {
      "time_zone": "UTC",
      "caller_rule_version": "example-v1",
      "weekly": {
        "mon": [
          {
            "start": "09:00",
            "end": "17:00"
          }
        ]
      },
      "overrides": [],
      "closures": [],
      "gap_policy": "reject",
      "overlap_policy": "earlier"
    },
    "range_start_date": "2025-01-06",
    "range_end_date": "2025-01-07",
    "instant_epoch_second": 1736154000
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/working-hours-contains/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"calendar":{"time_zone":"UTC","caller_rule_version":"example-v1","weekly":{"mon":[{"start":"09:00","end":"17:00"}]},"overrides":[],"closures":[],"gap_policy":"reject","overlap_policy":"earlier"},"range_start_date":"2025-01-06","range_end_date":"2025-01-07","instant_epoch_second":1736154000}'

The machine-readable contract is at /v1/tools/working-hours-contains/versions/1.0.0.

CLI

node cli.mjs run working-hours-contains 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

Related tools

• Working hours expand: Expand versioned weekly work schedules, overrides, closures, and DST policies into exact UTC intervals.
• Working hours total: Total exact elapsed seconds in a versioned working-hours calendar after DST and closure expansion.
• Appointment request check: Check an appointment request against pinned time-zone facts and caller-supplied booking rules.
• Duration application check: Check a claimed timestamp from adding or subtracting an ISO 8601 duration under explicit offset and month-end rules.
• ISO date range contains: Test whether an inclusive [start, end] date range contains a given date.
• ISO date add months: Add a signed month count to a YYYY-MM-DD date, clamping the day to the target month.