Publish a LinkedIn post as the connected member

What it does

Publish a LinkedIn post as the connected member, optionally with one uploaded image, video or document

Request

Body

Field	Type	Required	Description
`accountId`	string	no	Which connected LinkedIn account to post as, when more than one is connected
`altText`	string	no	Accessibility text, for an image
`commentary`	string	yes	The post text. LinkedIn allows up to 3000 characters.
`disableReshare`	boolean	no	Prevent other members from resharing this post
`lifecycleState`	enum	no	PUBLISHED posts immediately. DRAFT stages it invisibly; publish it later with PATCH. One of: PUBLISHED, DRAFT.
`mediaTitle`	string	no	Title shown with a video or document
`mediaUrn`	string	no	A urn:li:image / urn:li:video / urn:li:document returned by POST /v1/linkedin/media/upload
`visibility`	enum	no	Who can see the post. PUBLIC is anyone, CONNECTIONS is the member's connections, LOGGED_IN is any signed-in LinkedIn user. One of: PUBLIC, CONNECTIONS, LOGGED_IN.

Example request

{
  "accountId": "acc_634126",
  "altText": "Hello from castomAPI.",
  "commentary": "<commentary>",
  "disableReshare": false,
  "lifecycleState": "PUBLISHED",
  "mediaTitle": "Quarterly report",
  "mediaUrn": "example",
  "visibility": "PUBLIC"
}

Response

Field	Type	Description
`post`	object
`↳ authorUrn`	string
`↳ lifecycleState`	string
`↳ postUrn`	string
`↳ visibility`	string
`status`	string
`tokensDeducted`	integer

Example response

{
  "post": {
    "authorUrn": "Ada Lovelace",
    "lifecycleState": "<lifecycle state>",
    "postUrn": "example",
    "visibility": "<visibility>"
  },
  "status": "success",
  "tokensDeducted": 1
}

Errors

Every error answers with the same envelope: an HTTP status, a machine code and a sentence.

`400`	The body or a parameter failed validation. The details array names the field.
`401`	No key, a revoked key or a wrong header. Send x-api-key.
`402`	The wallet cannot cover this call. Top up or wait for the monthly grant.
`404`	The resource does not exist, or it is not yours. Both answer identically and cost nothing.
`429`	Over the per-minute quota of your tier. Back off and retry.
`5xx`	Upstream refused or timed out. The call is not billed.

Code

curl -X POST 'https://app.castomapi.com/v1/linkedin/posts' \
  -H 'x-api-key: <your-api-key>' \
  -H 'Content-Type: application/json' \
  -d '{"accountId": "acc_634126", "altText": "Hello from castomAPI.", "commentary": "<commentary>", "disableReshare": false, "lifecycleState": "PUBLISHED", "mediaTitle": "Quarterly report", "mediaUrn": "example", "visibility": "PUBLIC"}'

const res = await fetch('https://app.castomapi.com/v1/linkedin/posts', {
  method: 'POST',
  headers: { 'x-api-key': '<your-api-key>', 'Content-Type': 'application/json' },
  body: JSON.stringify({"accountId": "acc_634126", "altText": "Hello from castomAPI.", "commentary": "<commentary>", "disableReshare": false, "lifecycleState": "PUBLISHED", "mediaTitle": "Quarterly report", "mediaUrn": "example", "visibility": "PUBLIC"})
});
const data = await res.json();
console.log(data);

import { request } from 'node:https';

// Node 18+ has fetch built in
const res = await fetch('https://app.castomapi.com/v1/linkedin/posts', {
  method: 'POST',
  headers: { 'x-api-key': '<your-api-key>', 'Content-Type': 'application/json' },
  body: JSON.stringify({"accountId": "acc_634126", "altText": "Hello from castomAPI.", "commentary": "<commentary>", "disableReshare": false, "lifecycleState": "PUBLISHED", "mediaTitle": "Quarterly report", "mediaUrn": "example", "visibility": "PUBLIC"})
});
const data = await res.json();
console.log(data);

import requests

res = requests.post(
    'https://app.castomapi.com/v1/linkedin/posts',
    headers={'x-api-key': '<your-api-key>'},
    json={"accountId": "acc_634126", "altText": "Hello from castomAPI.", "commentary": "<commentary>", "disableReshare": False, "lifecycleState": "PUBLISHED", "mediaTitle": "Quarterly report", "mediaUrn": "example", "visibility": "PUBLIC"},
    timeout=30,
)
print(res.json())

<?php
$ch = curl_init('https://app.castomapi.com/v1/linkedin/posts');
curl_setopt_array($ch, [
    CURLOPT_CUSTOMREQUEST => 'POST',
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => ['x-api-key: <your-api-key>', 'Content-Type: application/json'],
    CURLOPT_POSTFIELDS => json_encode(['accountId' => 'acc_634126', 'altText' => 'Hello from castomAPI.', 'commentary' => '<commentary>', 'disableReshare' => false, 'lifecycleState' => 'PUBLISHED', 'mediaTitle' => 'Quarterly report', 'mediaUrn' => 'example', 'visibility' => 'PUBLIC']),
]);
$data = json_decode(curl_exec($ch), true);
print_r($data);

Cost and limits

This operation costs 1 token. A call that fails is never billed. Every account gets 1000 free tokens a month; paid balances never expire.

Rate limits per minute

No key	10
Free	60
Pro	300
Enterprise	1200

Docs → Pricing

Questions

What does Publish a LinkedIn post as the connected member cost?

1 token per successful call, debited from your wallet after the response. Failed calls are free. Every account receives 1000 free tokens a month.

How do I authenticate?

Send your key in the x-api-key header. One key covers every metered endpoint; there is nothing to enable per endpoint.

Can I send an Authorization: Bearer token instead?

Not for a metered endpoint — those take the x-api-key header and nothing else. Bearer tokens belong to the account side: the dashboard and account APIs accept a JWT session, and castomapi-auth issues those through a standard OAuth2 handshake, with authorization code, client credentials and refresh grants. The auth service page covers it.

What are the limits?

10 requests a minute per IP with no key at all, 60 a minute on the free tier, 300 on Pro, 1200 on Enterprise. Above the no-key tier the quota is per account, across every endpoint.

OpenAPI: https://app.castomapi.com/docs/json

Request

Response

What it does

Request

Body

Example request

Response

Example response

Errors

Code

Cost and limits

Rate limits per minute

Questions

More in LinkedIn

Where it fits