> ## Documentation Index
> Fetch the complete documentation index at: https://apidoc.bulkneo.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Send buttons
> POST /v1/messages/buttons — up to three tappable buttons.
**Best effort.** Many WhatsApp clients no longer render interactive messages and will show a plain-text fallback instead. A `200` means the message was accepted for delivery — **not** that the buttons will appear. The response carries `"best_effort": true` to say so explicitly. Read [Buttons and lists are best-effort](/guides/interactive-messages) before you build anything on this.
## Notes
* **1 to 3 buttons.** WhatsApp will not render more than three.
* `title` is required, up to 1,024 characters. `description` (up to 1,024) and `footer` (up to 60) are optional.
* `text` is the button label, 1–24 characters, required on every button.
**Each `type` needs one extra field:**
| `type` | Extra field | Rules |
| ------- | -------------- | ----------------------------------------------------------------------------------------------------------------------------------------- |
| `reply` | `id` | Required. 1–200 characters. Must be unique within the message. |
| `url` | `url` | Required. A public `http(s)` link — private, internal and loopback addresses are refused, as are links containing a username or password. |
| `call` | `phone_number` | Required. With country code. |
Only `reply`, `url` and `call` are accepted. Sending anything else returns `400 invalid_request` listing the allowed values.
## Example
```bash cURL theme={null}
curl -X POST https://api.bulkneo.com/v1/messages/buttons \
-H "apikey: YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"instance_id": "YOUR_INSTANCE_ID",
"to": "919876543210",
"title": "Confirm your order",
"description": "Order #2043 — ₹1,299",
"footer": "Reply STOP to opt out",
"buttons": [
{ "type": "reply", "text": "Confirm", "id": "confirm_2043" },
{ "type": "url", "text": "View order", "url": "https://example.com/orders/2043" },
{ "type": "call", "text": "Call us", "phone_number": "919812345678" }
]
}'
```
## The response
```json theme={null}
{
"success": true,
"data": {
"instance_id": "3f9c1a2b-7d4e-4c81-9f0a-2b6d5e8c1a34",
"to": "919876543210",
"type": "buttons",
"status": "sent",
"message_id": "3EB0C1D2F4A5B6C7D8E9",
"provider_status": "PENDING",
"best_effort": true,
"note": "Interactive messages are best-effort: many WhatsApp clients no longer render them and may show a plain-text fallback instead. …"
},
"request_id": "b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d"
}
```
**You cannot receive the tap.** When someone presses a reply button, the response goes into the WhatsApp conversation — there is no webhook and no endpoint that delivers it to your system. If you need the answer in software, ask for a typed reply instead.
## OpenAPI
````yaml api-reference/openapi.json POST /v1/messages/buttons
openapi: 3.1.0
info:
title: BulkNeo WhatsApp API
version: 1.0.0
description: >-
Send WhatsApp messages from your own connected numbers. Every request is
authenticated with an `apikey` header and names the `instance_id` of the
number it should be sent from.
servers:
- url: https://api.bulkneo.com
description: BulkNeo API
security:
- apikey: []
tags:
- name: Messages
description: Send a message from one of your connected numbers.
- name: Numbers
description: Check which numbers are reachable on WhatsApp.
- name: Instances
description: Create, connect, inspect and remove your WhatsApp numbers.
- name: Service
description: Unauthenticated service health checks.
paths:
/v1/messages/buttons:
post:
tags:
- Messages
summary: Send buttons
description: >-
Sends up to three tappable buttons: a quick reply, a link, or a call.
BEST EFFORT — many WhatsApp clients no longer render interactive
messages and show a plain-text fallback instead. A 200 means the message
was accepted for delivery, not that the buttons will appear.
operationId: sendButtons
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- instance_id
- to
- title
- buttons
properties:
instance_id:
$ref: '#/components/schemas/InstanceId'
to:
$ref: '#/components/schemas/Recipient'
title:
type: string
minLength: 1
maxLength: 1024
description: Heading of the message.
example: Confirm your order
description:
type: string
maxLength: 1024
description: Body text under the title.
example: 'Order #2043 — ₹1,299'
footer:
type: string
maxLength: 60
description: Small print under the buttons. Up to 60 characters.
buttons:
type: array
minItems: 1
maxItems: 3
description: 1 to 3 buttons. WhatsApp will not render more than three.
items:
type: object
required:
- type
- text
properties:
type:
type: string
enum:
- reply
- url
- call
description: What the button does when tapped.
text:
type: string
minLength: 1
maxLength: 24
description: The button label. Up to 24 characters.
example: Confirm
id:
type: string
maxLength: 200
description: >-
Required when `type` is `reply`. Identifies the button
when it is tapped; must be unique within the message.
example: confirm_2043
url:
type: string
maxLength: 2048
description: >-
Required when `type` is `url`. A public http(s) link —
private, internal and loopback addresses are refused,
and credentials in the URL are refused.
example: https://example.com/orders/2043
phone_number:
type: string
description: Required when `type` is `call`. With country code.
example: '919812345678'
quoted_message_id:
$ref: '#/components/schemas/QuotedMessageId'
quoted_from_me:
$ref: '#/components/schemas/QuotedFromMe'
example:
instance_id: 3f9c1a2b-7d4e-4c81-9f0a-2b6d5e8c1a34
to: '919876543210'
title: Confirm your order
description: 'Order #2043 — ₹1,299'
buttons:
- type: reply
text: Confirm
id: confirm_2043
- type: url
text: View order
url: https://example.com/orders/2043
- type: call
text: Call us
phone_number: '919812345678'
responses:
'200':
$ref: '#/components/responses/InteractiveSendSuccess'
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
'402':
$ref: '#/components/responses/PaymentRequired'
'403':
$ref: '#/components/responses/Forbidden'
'404':
$ref: '#/components/responses/InstanceNotFound'
'409':
$ref: '#/components/responses/NotConnected'
'422':
$ref: '#/components/responses/Unprocessable'
'429':
$ref: '#/components/responses/RateLimited'
'500':
$ref: '#/components/responses/InternalError'
'502':
$ref: '#/components/responses/UpstreamUnavailable'
components:
schemas:
InstanceId:
type: string
format: uuid
description: >-
Which of your connected numbers to send FROM. Copy it from your numbers
screen in the portal, or from `GET /v1/instances`. It must belong to
your account.
example: 3f9c1a2b-7d4e-4c81-9f0a-2b6d5e8c1a34
Recipient:
type: string
description: >-
The recipient, with country code and no leading zero — for example
`919876543210`. Spaces, dashes, brackets and a leading `+` are accepted
and stripped; 6 to 15 digits must remain.
example: '919876543210'
QuotedMessageId:
type: string
maxLength: 128
description: >-
Send this message as a reply, quoting an earlier one. Use the
`data.message_id` returned by a previous send.
example: 3EB0C1D2F4A5B6C7D8E9
QuotedFromMe:
type: boolean
default: false
description: >-
Set `true` when the quoted message is one you sent from this number.
Only valid together with `quoted_message_id`.
SendData:
type: object
properties:
instance_id:
type: string
format: uuid
to:
type: string
type:
type: string
description: The message type you sent.
status:
type: string
description: Always `sent` — the message was accepted for delivery.
message_id:
type:
- string
- 'null'
description: >-
The message's own id. Keep it: it is what you quote or react to
later.
provider_status:
type:
- string
- 'null'
description: >-
The delivery state at the moment of sending, for example `PENDING`.
It is a snapshot, not a delivery receipt.
Error:
type: object
properties:
success:
type: boolean
const: false
error:
type: object
properties:
code:
type: string
description: >-
Stable machine-readable code. Branch on this, not on the
message.
message:
type: string
description: Human-readable explanation. The wording may change.
details:
type: object
description: Extra safe context, present on some errors.
request_id:
type: string
format: uuid
description: Quote this when asking support about a request.
responses:
InteractiveSendSuccess:
description: >-
Accepted for delivery — best effort. `best_effort` and `note` are on
every interactive response, because whether the recipient's WhatsApp
renders it is outside anyone's control.
headers:
X-RateLimit-Scope:
$ref: '#/components/headers/RateLimitScope'
X-RateLimit-Limit:
$ref: '#/components/headers/RateLimitLimit'
X-RateLimit-Remaining:
$ref: '#/components/headers/RateLimitRemaining'
X-RateLimit-Reset:
$ref: '#/components/headers/RateLimitReset'
content:
application/json:
schema:
type: object
properties:
success:
type: boolean
const: true
data:
allOf:
- $ref: '#/components/schemas/SendData'
- type: object
properties:
best_effort:
type: boolean
const: true
note:
type: string
request_id:
type: string
format: uuid
example:
success: true
data:
instance_id: 3f9c1a2b-7d4e-4c81-9f0a-2b6d5e8c1a34
to: '919876543210'
type: buttons
status: sent
message_id: 3EB0C1D2F4A5B6C7D8E9
provider_status: PENDING
best_effort: true
note: >-
Interactive messages are best-effort: many WhatsApp clients no
longer render them and may show a plain-text fallback instead. A
successful response means the message was accepted for delivery,
not that the buttons will appear. Do not depend on it for
anything critical — send a text message with clear instructions
as a fallback.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
BadRequest:
description: >-
`invalid_request` a field is missing or malformed (the message names it,
including its position in a list) · `invalid_media_url` the `url` is not
a public http(s) link to a file.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: invalid_request
message: Field "text" is required and must be a non-empty string.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
Unauthorized:
description: >-
`missing_api_key` no `apikey` header was sent · `invalid_api_key` the
key is unknown or revoked.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: invalid_api_key
message: Invalid or revoked API key.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
PaymentRequired:
description: >-
`no_active_subscription` no usable plan on this account ·
`subscription_expired` the plan has run out.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: subscription_expired
message: >-
Your subscription has expired. Renew it to continue sending
messages.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
Forbidden:
description: >-
`account_suspended` · `access_expired` · `trial_quota_exceeded` ·
`instance_limit_reached` · `activation_unavailable`.
On `instance_limit_reached`, `details.limit_source` tells you which cap
you hit: `plan` (the plan you are on — upgrade it) or `account` (a cap
set on your account — ask your provider to raise it). Branch on that,
never on the wording of the message.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: trial_quota_exceeded
message: >-
Trial message quota reached (500 messages). Upgrade to a paid
plan to keep sending.
details:
trial_message_limit: 500
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
InstanceNotFound:
description: >-
`instance_not_found` — no such instance on your account. The same answer
is given for an id that does not exist and one that belongs to someone
else.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: instance_not_found
message: >-
Instance not found. Check the instance_id and that it belongs to
your account.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
NotConnected:
description: >-
`instance_not_connected` — the number is not connected. Do not retry:
pause and have someone re-scan the QR.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: instance_not_connected
message: >-
This WhatsApp instance is not connected. Connect it before
sending messages.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
Unprocessable:
description: '`invalid_recipient` — the recipient is not a valid WhatsApp number.'
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: invalid_recipient
message: The recipient number is not a valid WhatsApp number.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
RateLimited:
description: >-
`rate_limit_exceeded` — too many requests this minute. Wait for the
number of seconds in the `Retry-After` header. `details.scope` and the
`X-RateLimit-Scope` header say WHICH allowance you exceeded.
headers:
Retry-After:
description: Seconds to wait before retrying.
schema:
type: integer
X-RateLimit-Scope:
$ref: '#/components/headers/RateLimitScope'
X-RateLimit-Limit:
$ref: '#/components/headers/RateLimitLimit'
X-RateLimit-Remaining:
$ref: '#/components/headers/RateLimitRemaining'
X-RateLimit-Reset:
$ref: '#/components/headers/RateLimitReset'
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: rate_limit_exceeded
message: Rate limit exceeded, retry in 12s.
details:
retry_after_seconds: 12
limit_per_minute: 20
scope: messages
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
InternalError:
description: >-
`internal_error` — something went wrong on our side. Quote the
`request_id` to support.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: internal_error
message: An unexpected error occurred.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
UpstreamUnavailable:
description: >-
`upstream_unavailable` — the messaging service is temporarily
unavailable. Safe to retry after a short pause.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
example:
success: false
error:
code: upstream_unavailable
message: >-
The messaging service is temporarily unavailable. Please retry
shortly.
request_id: b1f2c3d4-5e6f-4a7b-8c9d-0e1f2a3b4c5d
headers:
RateLimitScope:
description: >-
WHICH allowance the other X-RateLimit-* headers describe. `messages`
covers every /v1/messages/* endpoint and /v1/numbers/check together;
`instances` is the separate, much larger budget for /v1/instances/*. If
you cache a limit, cache it against its scope.
schema:
type: string
enum:
- messages
- instances
example: messages
RateLimitLimit:
description: Requests allowed per minute on this scope.
schema:
type: integer
example: 20
RateLimitRemaining:
description: Requests left in the current minute on this scope.
schema:
type: integer
example: 17
RateLimitReset:
description: >-
Seconds until the allowance next goes up by one. Present on successful
responses too, so you can pace yourself without first earning a 429. The
window is a rolling minute, so this is when the oldest request ages out
— not a fixed reset instant. If `X-RateLimit-Remaining` is above 0 you
can send now.
schema:
type: integer
example: 43
securitySchemes:
apikey:
type: apiKey
in: header
name: apikey
description: >-
Your API key, sent in an `apikey` request header. Never in the URL,
never as a Bearer token.
````