> ## Documentation Index
> Fetch the complete documentation index at: https://docs.keebai.com/llms.txt
> Use this file to discover all available pages before exploring further.
# POST /v1/blocks/response-format
> Create a response format block with its content as plain text.
How the assistant writes: message length, emoji usage, and formatting rules. Separate from what it says, so you can change the voice without touching the content.
The block is created in the project catalogue and is **not attached to anything**. Wire it into an assistant with [`POST /v1/assistants/{id}/blocks`](/dev/endpoints/assistants-block-attach) afterwards.
**Identity block: one per assistant.** A second `response_format` on the same assistant fails with `ASSISTANT_DUPLICATE_IDENTITY_BLOCK`.
## Endpoint
```
POST https://api.keebai.com/v1/blocks/response-format
```
## Required scope
`assistants:write`
## Headers
| Header | Required | Value |
| --------------- | -------- | ------------------------ |
| `Authorization` | Yes | `Bearer kbai_pk_` |
| `Content-Type` | Yes | `application/json` |
## Body
| Field | Type | Required | Description |
| --------- | -------- | -------- | ----------------------------------------------------------------------------- |
| `name` | `string` | Yes | Up to 150 characters. What the block shows as in the portal. |
| `content` | `string` | No | The block's text, up to 100,000 characters. Omit it to create an empty block. |
`type` and `family` are not accepted: the type is the endpoint you called, and `family` is derived from it (`identity` for this one).
## Example request
```bash curl theme={null}
curl -X POST https://api.keebai.com/v1/blocks/response-format \
-H "Authorization: Bearer kbai_pk_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \
-H "Content-Type: application/json" \
-d '{
"name": "Formato de respuesta",
"content": "- Máximo tres líneas por mensaje.\n- Un emoji por mensaje como mucho.\n- Nunca usar listas con viñetas en WhatsApp.\n- Los precios van con separador de miles."
}'
```
```js JavaScript theme={null}
const resp = await fetch("https://api.keebai.com/v1/blocks/response-format", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.KEEBAI_API_TOKEN}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
name: "Formato de respuesta",
content: "- Máximo tres líneas por mensaje.\n- Un emoji por mensaje como mucho.\n- Nunca usar listas con viñetas en WhatsApp.\n- Los precios van con separador de miles.",
}),
});
const { block } = await resp.json();
// Then wire it into an assistant.
await fetch("https://api.keebai.com/v1/assistants/6650a1b2c3d4e5f6a7b8c9d0/blocks", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.KEEBAI_API_TOKEN}`,
"Content-Type": "application/json",
},
body: JSON.stringify({ block_id: block._id }),
});
```
```python Python theme={null}
import os, requests
resp = requests.post(
"https://api.keebai.com/v1/blocks/response-format",
headers={"Authorization": f"Bearer {os.environ['KEEBAI_API_TOKEN']}"},
json={"name": "Formato de respuesta", "content": "- Máximo tres líneas por mensaje.\n- Un emoji por mensaje como mucho."},
timeout=10,
)
resp.raise_for_status()
block = resp.json()["block"]
```
## Response
### 201 Created
```json theme={null}
{
"block": {
"_id": "6650bbbb2222cccc3333dddd",
"type": "response_format",
"family": "identity",
"name": "Formato de respuesta",
"current_version_id": "6650ffff4444aaaa5555bbbb",
"is_archived": false,
"content_writable": true,
"created_at": "2026-07-26T21:38:22.104Z",
"updated_at": "2026-07-26T21:38:22.104Z"
}
}
```
### 400 Bad Request
Missing `name`, `content` over 100,000 characters, or a property the endpoint does not accept.
### 401 Unauthorized
Missing, invalid, revoked, or expired token.
### 403 Forbidden
The token does not have the `assistants:write` scope.
### 502 Bad Gateway
The assistant service is unreachable.
## Operational notes
* Channel-specific rules belong here. The same assistant answering on WhatsApp and on web chat reads the same formatting block, so say which rule applies where.
* **Creating a block also creates its first version.** The response already carries a `current_version_id`, even when you omit `content` — the block starts with one empty version rather than none.
* **Creation is not idempotent.** Nothing enforces unique names, so a retry after a timeout leaves you with two blocks. Check [the catalogue](/dev/endpoints/blocks-list) filtered by `type` before retrying.
* **Content is plain text with three markdown conventions**: `-` for bullets, `1.` for numbered items, `#` for headings. Everything else is a paragraph. [More on how content is stored](/dev/assistants/overview#content-is-text).
* **The block belongs to the token's project**, and a token on another project can neither see it nor read it by id.
## OpenAPI
````yaml POST /v1/blocks/response-format
openapi: 3.0.0
info:
title: Keebai Public API
description: Superficie pública REST autenticada con Personal Access Tokens (PAT).
version: 1.0.0
contact: {}
servers:
- url: https://api.keebai.com
description: Production
security: []
tags: []
paths:
/v1/blocks/response-format:
post:
tags:
- blocks
summary: Crear un bloque de formato de respuesta
description: >-
Largo, uso de emojis y reglas de formato de los mensajes. Bloque de
identidad, uno por asistente.
operationId: PublicBlocksController_createResponseFormat
parameters: []
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/PublicBlockCreateDto'
responses:
'201':
description: ''
content:
application/json:
schema:
$ref: '#/components/schemas/PublicBlockEnvelopeDto'
security:
- PAT: []
components:
schemas:
PublicBlockCreateDto:
type: object
properties:
name:
type: string
maxLength: 150
description: Nombre con el que el bloque aparece en el portal.
example: Tono cercano
content:
type: string
maxLength: 100000
description: >-
Contenido inicial en texto. Se reconocen listas con '-' y con '1.',
y encabezados con '#'. Sin este campo el bloque nace vacio.
required:
- name
PublicBlockEnvelopeDto:
type: object
properties:
block:
$ref: '#/components/schemas/PublicBlockDto'
required:
- block
PublicBlockDto:
type: object
properties:
_id:
type: string
type:
type: string
enum:
- personification
- objective
- response_format
- steps
- cases_possible
- do_not
- product_info
- store_info
- reservation_info
- tables_info
- tags
- response_policy
family:
type: string
enum:
- identity
- instructions
- information
description: >-
Se deriva del tipo y determina en que seccion del prompt entra el
bloque. Es de solo lectura.
name:
type: string
current_version_id:
type: string
nullable: true
description: >-
Version vigente del bloque. Su contenido se lee en GET
/v1/blocks/{id}/content.
is_archived:
type: boolean
content_writable:
type: boolean
description: >-
Si el contenido de este bloque se puede editar por API. Los tipos de
catalogo son de solo lectura porque su escritura depende de una
sincronizacion de funciones que vive en el portal.
created_at:
type: string
updated_at:
type: string
required:
- _id
- type
- family
- name
- current_version_id
- is_archived
- content_writable
- created_at
- updated_at
securitySchemes:
PAT:
scheme: bearer
bearerFormat: kbai_pk_
type: http
description: >-
Personal Access Token con prefijo `kbai_pk_`. Generar desde el portal
con permiso `developer.manage_tokens`.
````