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Eigen Documentation

Writing Data

Historian Multi Write API is set of Ingenuity APIs for creating tags and writing timeseries data to ingenuity databases for use on the Ingenuity Platform

1. Authentication

Section titled “1. Authentication”

All requests need to be authenticated using API Key, passed as apikey query parameter or X-Api-Key HTTP header.

2. Limits

Section titled “2. Limits”

Write operations can only be performed on historians marked writable. Often this will not include Client production systems, as we maintain a read-only connection, so write data will be often need to be stored in a writable timeseries database local to the Ingenuity.

Details on listing the available Writable historians can be found with the List Historians method detailed below

3. Request Methods

Section titled “3. Request Methods”

All operations require a “writable” historian name, and a tag name

Some methods require a field of type “timestamp”, our APIs accept several formats for these values:

  • Most ISO Formats
    • 2026-04-22T23:59:49Z
    • 2026-04-22T21:59:49+02:00
    • 2026-04-22T21:59:49[Europe/Oslo]
  • Unix/Epoch Seconds or Milliseconds
    • 1776902389
    • 1776902389000
  • Relative Timestamps
    • now
    • yesterday
    • 4 hours ago
    • 7 days ago at 00:00
    • today at midnight

Request Paths

GET /historian/list

GET /historian/listwritable

Input Parameters N/A

Description

List all historians available on the Ingenuity Instance, or only the ones that are flagged as writeable

Example:

Result

All Historians:

{
  "historians": [
    {
      "name": "eigen_manual_input"
    },
    {
      "name": "IP21"
    }
  ]
}

Writable Historians:

{
  "historians": [
    {
      "name": "eigen_manual_input"
    }
  ]
}