> For the complete documentation index, see [llms.txt](https://docs.rootcause.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rootcause.ai/more-details/applications/application-modules/constant.md).

# Constant

> Emit one typed value.

Emits one literal value of `kind`. The scalar counterpart of a hard-coded number in a formula, and the usual right-hand side of a Compare.

## At a glance

|                          |                              |
| ------------------------ | ---------------------------- |
| Module type              | `Constant`                   |
| Category                 | Primitives · Scalar and json |
| Default tier             | `reactive`                   |
| Runs on                  | `reactive`, `durable`        |
| Starts a flow            | no                           |
| Holds a body             | no                           |
| Keeps state between runs | no                           |
| Available in             | every application type       |

## Parameters

### `value`

`string | number | boolean | null` · required · defaults to `null`

The literal to emit.

### `kind`

`"string" | "number" | "boolean" | "datetime"` · required · defaults to `"string"`

The type of the emitted value.

## Inputs

| Port | Kind    | Required | Description                                                                                                                           |
| ---- | ------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------- |
| `on` | `event` | no       | Implicit on every module that does not itself start a flow: wire an event here to make this module the start of what that event runs. |

## Outputs

| Port    | Kind     | Connects to                        | Description                   |
| ------- | -------- | ---------------------------------- | ----------------------------- |
| `value` | `scalar` | `scalar`, `json`, `text`, `signal` | The literal, typed by `kind`. |

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