Concepts

Data model

CorrConnect returns one kind of record today, an activity summary. Every activity has the same required fields; the optional ones depend on where it came from.

Activities

JSON

{
  "id": "act_0123456789abcdef0123456789abcdef",
  "source": "tcx",
  "activity_type": "run",
  "started_at": "2026-10-12T06:31:05Z",
  "duration_seconds": 2914.0,
  "duration_basis": "recorded_lap_sum",
  "distance_meters": 8012.4,
  "distance_basis": "recorded_lap_sum",
  "provenance": {"format": "TCX", "version": "2", "activity_index": 1},
  "laps": [
    {
      "index": 1,
      "started_at": "2026-10-12T06:31:05Z",
      "duration_seconds": 2914.0,
      "distance_meters": 8012.4,
      "tracks": [{"index": 1, "point_count": 2914, "started_at": "2026-10-12T06:31:05Z", "ended_at": "2026-10-12T07:19:39Z"}]
    }
  ],
  "created_at": "2026-10-12T08:02:44+00:00"
}

Field	Always there	Notes
`id`	Yes	`act_` and 32 hex characters. Stable for the life of the record.
`source`	Yes	Where it came from. See the table below.
`activity_type`	Yes	`run`, `ride`, `swim`, `walk`, `strength` or `other`.
`started_at`	Yes	ISO 8601 with a UTC offset.
`duration_seconds`	Yes	A number; files can give fractions of a second.
`created_at`	Yes	When CorrConnect stored it. Lists are ordered by this, newest first.
`distance_meters`	No	Missing, or `null`, when the source has no distance. Never estimated.
`title`	No	Missing or `null` when there isn't one.
`duration_basis`, `distance_basis`	No	How the number was measured, for example `recorded_lap_sum`.
`provenance`	No	The file format and the position of this activity in the file.
`laps`	No	TCX and FIT: per-lap start, duration and distance.
`segments`	No	GPX: per-segment point count, start, end and elapsed seconds.

New optional fields and new values for source and the basis fields can appear without notice. Ignore what you don't recognize, and don't fill gaps: a missing distance means the source didn't record one.

Sources

`source`	Comes from	What to expect
`manual_json`	A summary the athlete imported in the portal	`distance_meters` and `title` are present, possibly `null`. No basis fields.
`gpx`	A GPX 1.1 file	`activity_type` is always `other` (GPX has no sport). `duration_basis` is `derived_segment_elapsed_sum`. No distance. `title` from the track name. `segments`.
`tcx`	A TCX v2 file	`run`, `ride` or `other`. Duration and distance are `recorded_lap_sum`. `laps` with track point counts.
`fit`	A FIT activity file	Sport from the session: running, cycling, swimming, walking and strength training map to the five types; anything else is `other`. `recorded_session_total_elapsed_time`, and `recorded_session_total_distance` when recorded. `laps`.

One file can hold up to 20 activities (GPX tracks or TCX activities) or 20 FIT sessions; each becomes its own record. More about files in workout files.

What CorrConnect does not return

GPS coordinates. Files are checked for valid positions, but points are never stored or returned.
Sensor streams (heart rate, power, cadence by the second).
The original file. There is no download endpoint.
The athlete's email, name or CorrConnect account ID. You get the pairwise sub instead.

IDs

Prefix	What
`app_`	Your app's `client_id`
`act_`	Activity
`ccu_`	Athlete subject for your app (`sub`)
`evt_`	Webhook event; the same on every retry
`whs_`	Webhook subscription
`whd_`	One delivery of an event to one subscription
`req_`	Request ID on every response and error
`cca_`, `ccr_`, `ccc_`	Access token, refresh token, authorization code

IDs are opaque. Compare them as whole strings and don't derive anything from the characters after the prefix.

Times

Every timestamp is ISO 8601 with a UTC offset, so parse them with a full ISO 8601 parser. CorrConnect's own times (created_at, event times) end in +00:00. Times read from a GPX, TCX or FIT file are converted to UTC and end in Z. A manual_json summary keeps the offset the athlete sent, for example 2026-09-22T07:15:00-04:00.