---
title: "ModelCall"
description: "one call of a model, metered against the unit it served"
section: concepts
address: /concepts/modelcall
contract: 0476e35e6e275db5
---

# ModelCall

one call of a model, metered against the unit it served

[figure: ModelCall is a fact at follows scope. The drawing shows its fields and the objects that they point at.]

| property | value |
|---|---|
| kind | fact |
| scope | follows |
| key | the model, the unit and the moment |
| store | postgres+lake |
| family | models |



## Fields


| field | type | required | note |
|---|---|---|---|
| `model` | [Model](/concepts/model) | yes |  |
| `unit` | `id` | yes |  |
| `tokens` | `count` | no |  |
| `size` | `bytes` | no |  |
| `cost` | [Cost](/concepts/cost) | yes |  |
| `outcome` | `one of answered \| refused \| failed` | yes |  |
| `run` | `id` | yes |  |



## Routes that use it
No route takes or returns ModelCall directly. The record holds it, and the objects that point at it reach it.