---
title: "act: parameter"
description: "a parameter by its name, its value and its scope to the parameter as written, at its new version"
section: reference
address: /reference/act/parameter
contract: 0476e35e6e275db5
---
# act: parameter
a parameter by its name, its value and its scope to the parameter as written, at its new version
[figure: The caller sends ParameterWriteInput to /v1/act/parameter. The platform returns a card whose body is Parameter.]
POST/v1/act/parameter
Change a setting. The call needs the user rung under a token with the act grant, and it is served by the platform.
The route takes [ParameterWriteInput](/concepts/parameterwriteinput) and returns a card whose body is [Parameter](/concepts/parameter).
## Request body
The request body is [ParameterWriteInput](/concepts/parameterwriteinput).
| field | type | required | note |
|---|---|---|---|
| `name` | `text` | yes | |
| `value` | `json` | yes | |
| `scope` | [Scope](/concepts/scope) | no | the caller's tenant when absent |
## Response
The route returns a card whose body is [Parameter](/concepts/parameter). Every card ends with a foot that states the basis of each number, the scope of the call, and the time when the facts were true.
## Headers
| header | required | meaning |
|---|---|---|
| `Scale-Scope` | yes | the scope the call runs in: tenant/, then /brand/, then /strategy/ |
| `Scale-As-True-On` | no | the date the facts must have been true on; defaults to now |
| `Scale-As-Known-On` | no | the date the facts must have been known on; defaults to now |
| `Scale-Key` | no | for a change, the key made from the input; a repeat under the same key returns the unit held and writes nothing |
A caller needs the user rung and a token with the act grant. The platform serves this route.
## Example
The example sends the smallest body that ParameterWriteInput allows. The build validates it against the schema of ParameterWriteInput.
Example
```sh
curl -X POST https://api.scaleintelligence.co/v1/act/parameter \
-H "Scale-Key: $SCALE_KEY" -H "Scale-Scope: tenant/" \
-H "content-type: application/json" \
-d '{ "name": "…", "value": null }'
```
```typescript
import { client } from "@scale/sdk";
const answer = await client.act.parameter({
"name": "…",
"value": null
});
// answer.body is a Parameter. answer.foot holds the basis, the scope and the time.
```
```python
import requests
answer = requests.post("https://api.scaleintelligence.co/v1/act/parameter",
headers={"Scale-Key": KEY, "Scale-Scope": "tenant/"},
json={
"name": "…",
"value": null
}).json()
```
```rust
let answer: Card = client.post("https://api.scaleintelligence.co/v1/act/parameter")
.header("Scale-Key", key).header("Scale-Scope", "tenant/")
.json(&ParameterWriteInput { /* the fields of the page */ }).send().await?.json().await?;
```