> ## Documentation Index
> Fetch the complete documentation index at: https://docs.truemath.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Provenance

> Every variable value records where it came from — user-stated, calculated, carried forward, or default. Provenance is what makes a result accountable.

**Provenance** is the record of where a [variable's](/concepts/variables) value came
from. Every value TrueMath works with carries this metadata, so a result is not just a
number — it is a number you can trace back to its origin.

## Kinds of provenance

A value's origin is one of:

* **User-stated** — provided directly as an input.
* **Calculated** — computed by an [activity](/concepts/activities) from other values.
* **Carried forward** — brought forward from an earlier point in the same
  [conversation](/concepts/scenarios).
* **Default** — supplied from the variable's default value.

In API results, each variable reports a `source` of `user_input`, `calculated`, or
`default_value`, and a `historical` flag indicating whether the value was carried
forward from a prior [scenario](/concepts/scenarios).

## Resolution

When more than one value could apply to a variable, TrueMath resolves it
deterministically — the same inputs always produce the same result — and every
resolved value keeps the provenance record described above, so you can always see
which value was used and where it came from. A **default is a fallback**: it applies
only when no other value has been provided or calculated for that variable.

## Why it matters

Because every value's origin is tracked through each step, a calculation can be
explained as a sequence of documented inputs and results rather than presented as an
unaccountable answer. Provenance is the foundation of that explainability — and a core
part of what makes TrueMath an execution layer you can trust. See
[Guarantees](/introduction/guarantees).