Local interval normalize

local-interval-normalize · version 1.0.0 · Dates & times (UTC, ISO 8601) · free, no key needed

Normalize millisecond interval endpoint conventions into a canonical half-open interval.

Use when you need to: normalize interval endpoints · convert closed interval to half open · canonicalize millisecond interval.

Decide before calling

Read the versioned contract and the supported scope below. Reuse local-interval-normalize@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 local-interval-normalize@1.0.0 for normalize interval endpoints. 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

• normalize interval endpoints
• convert closed interval to half open
• canonicalize millisecond interval
• normalize inclusive end boundary
• normalize exclusive start boundary
• detect empty normalized interval

Not supported

• generic date arithmetic
• resolve a local time zone
• continuous-number endpoint normalization

Behavior

• Integer milliseconds form a discrete domain; ( adds one millisecond to start and ] adds one millisecond to end.
• Output is always the half-open interval [start_ms,end_ms).
• A normalized start after end is not_computable; equality is an empty interval.
• Caller endpoint rules are versioned by caller_rule_version.

Input

• start_ms (string, required): min length 1; max length 32; pattern ^-?(?:0|[1-9]\d*)$
• end_ms (string, required): min length 1; max length 32; pattern ^-?(?:0|[1-9]\d*)$
• endpoint_convention (one of "[)", "[]", "()", "(]", required)
• caller_rule_version (string, required): min length 1; max length 64

Output

• standard_version (string, required)
• data_version (string, required)
• caller_rule_version (string, required)
• start_ms (string, required)
• end_ms (string, required)
• endpoint_convention (constant "[)", required)
• empty (boolean, required)

Limits

• max input bytes: 4096
• max integer chars: 32

Example

Request input:

{
  "start_ms": "10",
  "end_ms": "20",
  "endpoint_convention": "[]",
  "caller_rule_version": "r1"
}

Response:

{
  "result": {
    "standard_version": "RFC9557/RFC3339/ISO8601-1:2019",
    "data_version": "iana-tzdb-2025b-subset-nyc",
    "caller_rule_version": "r1",
    "start_ms": "10",
    "end_ms": "21",
    "empty": false,
    "endpoint_convention": "[)"
  }
}

How to call it

MCP

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

{
  "id": "local-interval-normalize",
  "version": "1.0.0",
  "input": {
    "start_ms": "10",
    "end_ms": "20",
    "endpoint_convention": "[]",
    "caller_rule_version": "r1"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/local-interval-normalize/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"start_ms":"10","end_ms":"20","endpoint_convention":"[]","caller_rule_version":"r1"}'

The machine-readable contract is at /v1/tools/local-interval-normalize/versions/1.0.0.

CLI

node cli.mjs run local-interval-normalize 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

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