Send LinkedIn message
curl --request POST \
--url https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--header 'Team-SID: <api-key>' \
--data '
{
"linkedin_account_sid": "<string>",
"text": "<string>",
"linkedin_conversation_sid": "<string>",
"ln_id": "<string>",
"sn_id": "<string>",
"attachments": [
{
"file_base64": "<string>",
"file_url": "<string>",
"file_name": "<string>",
"file_type": "<string>",
"file_byte_size": 2
}
],
"client_reference": "<string>"
}
'import requests
url = "https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send"
payload = {
"linkedin_account_sid": "<string>",
"text": "<string>",
"linkedin_conversation_sid": "<string>",
"ln_id": "<string>",
"sn_id": "<string>",
"attachments": [
{
"file_base64": "<string>",
"file_url": "<string>",
"file_name": "<string>",
"file_type": "<string>",
"file_byte_size": 2
}
],
"client_reference": "<string>"
}
headers = {
"Authorization": "Bearer <token>",
"Team-SID": "<api-key>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {
Authorization: 'Bearer <token>',
'Team-SID': '<api-key>',
'Content-Type': 'application/json'
},
body: JSON.stringify({
linkedin_account_sid: '<string>',
text: '<string>',
linkedin_conversation_sid: '<string>',
ln_id: '<string>',
sn_id: '<string>',
attachments: [
{
file_base64: '<string>',
file_url: '<string>',
file_name: '<string>',
file_type: '<string>',
file_byte_size: 2
}
],
client_reference: '<string>'
})
};
fetch('https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'linkedin_account_sid' => '<string>',
'text' => '<string>',
'linkedin_conversation_sid' => '<string>',
'ln_id' => '<string>',
'sn_id' => '<string>',
'attachments' => [
[
'file_base64' => '<string>',
'file_url' => '<string>',
'file_name' => '<string>',
'file_type' => '<string>',
'file_byte_size' => 2
]
],
'client_reference' => '<string>'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"Content-Type: application/json",
"Team-SID: <api-key>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send"
payload := strings.NewReader("{\n \"linkedin_account_sid\": \"<string>\",\n \"text\": \"<string>\",\n \"linkedin_conversation_sid\": \"<string>\",\n \"ln_id\": \"<string>\",\n \"sn_id\": \"<string>\",\n \"attachments\": [\n {\n \"file_base64\": \"<string>\",\n \"file_url\": \"<string>\",\n \"file_name\": \"<string>\",\n \"file_type\": \"<string>\",\n \"file_byte_size\": 2\n }\n ],\n \"client_reference\": \"<string>\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
req.Header.Add("Team-SID", "<api-key>")
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send")
.header("Authorization", "Bearer <token>")
.header("Team-SID", "<api-key>")
.header("Content-Type", "application/json")
.body("{\n \"linkedin_account_sid\": \"<string>\",\n \"text\": \"<string>\",\n \"linkedin_conversation_sid\": \"<string>\",\n \"ln_id\": \"<string>\",\n \"sn_id\": \"<string>\",\n \"attachments\": [\n {\n \"file_base64\": \"<string>\",\n \"file_url\": \"<string>\",\n \"file_name\": \"<string>\",\n \"file_type\": \"<string>\",\n \"file_byte_size\": 2\n }\n ],\n \"client_reference\": \"<string>\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Team-SID"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"linkedin_account_sid\": \"<string>\",\n \"text\": \"<string>\",\n \"linkedin_conversation_sid\": \"<string>\",\n \"ln_id\": \"<string>\",\n \"sn_id\": \"<string>\",\n \"attachments\": [\n {\n \"file_base64\": \"<string>\",\n \"file_url\": \"<string>\",\n \"file_name\": \"<string>\",\n \"file_type\": \"<string>\",\n \"file_byte_size\": 2\n }\n ],\n \"client_reference\": \"<string>\"\n}"
response = http.request(request)
puts response.read_body{
"success": true,
"operation": "action",
"action": "<string>",
"item": {
"sid": "<string>",
"team_sid": "<string>",
"linkedin_account_sid": "<string>",
"linkedin_conversation_sid": "<string>",
"messenger_type": "linkedin",
"linkedin_type": "message",
"type": "inbox",
"automation": "auto",
"ln_member_id": "<string>",
"ln_id": "<string>",
"sn_id": "<string>",
"talent_id": "<string>",
"nickname": "<string>",
"subject": "<string>",
"text": "<string>",
"client_reference": "<string>",
"attachments": [
{
"id": "<string>",
"urn": "<string>",
"name": "<string>",
"content_type": "<string>",
"content_url": "<string>",
"file_byte_size": 123,
"path": "<string>",
"size": 123
}
],
"reactions": [
{
"emoji": "<string>",
"count": 123,
"is_viewer_reacted": true,
"first_reacted_at": "<string>"
}
],
"is_deleted": true,
"message_hash": "<string>",
"sent_at": "<string>",
"custom_content": {},
"created_at": "<string>",
"updated_at": "<string>",
"deleted_at": "<string>"
},
"result": {},
"meta": {
"trace_id": "<string>",
"span_id": "<string>",
"timestamp": "<string>",
"duration_ms": 1,
"team_sid": "<string>",
"actor_type": "<string>"
}
}{
"success": false,
"error": {
"code": "validation_failed",
"message": "<string>",
"recoverable": true,
"suggestion": "<string>",
"field_errors": {},
"blockers": [
{
"type": "<string>",
"severity": "hard",
"description": "<string>",
"entity_sid": "<string>",
"resolution": "<string>",
"resolution_hint": "<string>",
"count": 123
}
],
"context": {}
},
"meta": {
"trace_id": "<string>",
"span_id": "<string>",
"timestamp": "<string>",
"duration_ms": 1,
"team_sid": "<string>",
"actor_type": "<string>"
}
}{
"success": false,
"error": {
"code": "validation_failed",
"message": "<string>",
"recoverable": true,
"suggestion": "<string>",
"field_errors": {},
"blockers": [
{
"type": "<string>",
"severity": "hard",
"description": "<string>",
"entity_sid": "<string>",
"resolution": "<string>",
"resolution_hint": "<string>",
"count": 123
}
],
"context": {}
},
"meta": {
"trace_id": "<string>",
"span_id": "<string>",
"timestamp": "<string>",
"duration_ms": 1,
"team_sid": "<string>",
"actor_type": "<string>"
}
}linkedin_messages
Send LinkedIn message
Send one outbound regular LinkedIn DM on the basic messenger (outward action). Reply to an existing thread via linkedin_conversation_sid, or open a new thread to a 1st-degree connection via ln_id / sn_id. Guards run first: in-flight dedup, send_messages daily cap, 8000-char body cap, connection guard, attachment https:// reachability, basic-messenger surface guard. Fire-on-success: a row is inserted only on terminal success. When NOT: InMail to a non-connection → send_linkedin_inmail; voice note → send_linkedin_voice_message; Sales Navigator thread → send_linkedin_sales_nav_message; the connection-request note lives on linkedin-connection-requests. Bulk send: loop client-side and respect the daily cap.
Contract:
- MCP tool
send_linkedin_message, registry packagemcp.linkedin/linkedin_messages, mountlinkedin.messaging. - Operation
action, response envelopeaction. - Flags: dangerous: the MCP layer gates it behind a preview/commit token, and the effect cannot be undone through this API; step eligible: gtm.service.orchestration can run this verb as a mass-action plan step, once per item.
POST
/
api
/
linkedin-messages
/
send
Send LinkedIn message
curl --request POST \
--url https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--header 'Team-SID: <api-key>' \
--data '
{
"linkedin_account_sid": "<string>",
"text": "<string>",
"linkedin_conversation_sid": "<string>",
"ln_id": "<string>",
"sn_id": "<string>",
"attachments": [
{
"file_base64": "<string>",
"file_url": "<string>",
"file_name": "<string>",
"file_type": "<string>",
"file_byte_size": 2
}
],
"client_reference": "<string>"
}
'import requests
url = "https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send"
payload = {
"linkedin_account_sid": "<string>",
"text": "<string>",
"linkedin_conversation_sid": "<string>",
"ln_id": "<string>",
"sn_id": "<string>",
"attachments": [
{
"file_base64": "<string>",
"file_url": "<string>",
"file_name": "<string>",
"file_type": "<string>",
"file_byte_size": 2
}
],
"client_reference": "<string>"
}
headers = {
"Authorization": "Bearer <token>",
"Team-SID": "<api-key>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {
Authorization: 'Bearer <token>',
'Team-SID': '<api-key>',
'Content-Type': 'application/json'
},
body: JSON.stringify({
linkedin_account_sid: '<string>',
text: '<string>',
linkedin_conversation_sid: '<string>',
ln_id: '<string>',
sn_id: '<string>',
attachments: [
{
file_base64: '<string>',
file_url: '<string>',
file_name: '<string>',
file_type: '<string>',
file_byte_size: 2
}
],
client_reference: '<string>'
})
};
fetch('https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send', options)
.then(res => res.json())
.then(res => console.log(res))
.catch(err => console.error(err));<?php
$curl = curl_init();
curl_setopt_array($curl, [
CURLOPT_URL => "https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 30,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "POST",
CURLOPT_POSTFIELDS => json_encode([
'linkedin_account_sid' => '<string>',
'text' => '<string>',
'linkedin_conversation_sid' => '<string>',
'ln_id' => '<string>',
'sn_id' => '<string>',
'attachments' => [
[
'file_base64' => '<string>',
'file_url' => '<string>',
'file_name' => '<string>',
'file_type' => '<string>',
'file_byte_size' => 2
]
],
'client_reference' => '<string>'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"Content-Type: application/json",
"Team-SID: <api-key>"
],
]);
$response = curl_exec($curl);
$err = curl_error($curl);
curl_close($curl);
if ($err) {
echo "cURL Error #:" . $err;
} else {
echo $response;
}package main
import (
"fmt"
"strings"
"net/http"
"io"
)
func main() {
url := "https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send"
payload := strings.NewReader("{\n \"linkedin_account_sid\": \"<string>\",\n \"text\": \"<string>\",\n \"linkedin_conversation_sid\": \"<string>\",\n \"ln_id\": \"<string>\",\n \"sn_id\": \"<string>\",\n \"attachments\": [\n {\n \"file_base64\": \"<string>\",\n \"file_url\": \"<string>\",\n \"file_name\": \"<string>\",\n \"file_type\": \"<string>\",\n \"file_byte_size\": 2\n }\n ],\n \"client_reference\": \"<string>\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
req.Header.Add("Team-SID", "<api-key>")
req.Header.Add("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))
}HttpResponse<String> response = Unirest.post("https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send")
.header("Authorization", "Bearer <token>")
.header("Team-SID", "<api-key>")
.header("Content-Type", "application/json")
.body("{\n \"linkedin_account_sid\": \"<string>\",\n \"text\": \"<string>\",\n \"linkedin_conversation_sid\": \"<string>\",\n \"ln_id\": \"<string>\",\n \"sn_id\": \"<string>\",\n \"attachments\": [\n {\n \"file_base64\": \"<string>\",\n \"file_url\": \"<string>\",\n \"file_name\": \"<string>\",\n \"file_type\": \"<string>\",\n \"file_byte_size\": 2\n }\n ],\n \"client_reference\": \"<string>\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://app.gtm-api.com/linkedin/v4/api/linkedin-messages/send")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Team-SID"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"linkedin_account_sid\": \"<string>\",\n \"text\": \"<string>\",\n \"linkedin_conversation_sid\": \"<string>\",\n \"ln_id\": \"<string>\",\n \"sn_id\": \"<string>\",\n \"attachments\": [\n {\n \"file_base64\": \"<string>\",\n \"file_url\": \"<string>\",\n \"file_name\": \"<string>\",\n \"file_type\": \"<string>\",\n \"file_byte_size\": 2\n }\n ],\n \"client_reference\": \"<string>\"\n}"
response = http.request(request)
puts response.read_body{
"success": true,
"operation": "action",
"action": "<string>",
"item": {
"sid": "<string>",
"team_sid": "<string>",
"linkedin_account_sid": "<string>",
"linkedin_conversation_sid": "<string>",
"messenger_type": "linkedin",
"linkedin_type": "message",
"type": "inbox",
"automation": "auto",
"ln_member_id": "<string>",
"ln_id": "<string>",
"sn_id": "<string>",
"talent_id": "<string>",
"nickname": "<string>",
"subject": "<string>",
"text": "<string>",
"client_reference": "<string>",
"attachments": [
{
"id": "<string>",
"urn": "<string>",
"name": "<string>",
"content_type": "<string>",
"content_url": "<string>",
"file_byte_size": 123,
"path": "<string>",
"size": 123
}
],
"reactions": [
{
"emoji": "<string>",
"count": 123,
"is_viewer_reacted": true,
"first_reacted_at": "<string>"
}
],
"is_deleted": true,
"message_hash": "<string>",
"sent_at": "<string>",
"custom_content": {},
"created_at": "<string>",
"updated_at": "<string>",
"deleted_at": "<string>"
},
"result": {},
"meta": {
"trace_id": "<string>",
"span_id": "<string>",
"timestamp": "<string>",
"duration_ms": 1,
"team_sid": "<string>",
"actor_type": "<string>"
}
}{
"success": false,
"error": {
"code": "validation_failed",
"message": "<string>",
"recoverable": true,
"suggestion": "<string>",
"field_errors": {},
"blockers": [
{
"type": "<string>",
"severity": "hard",
"description": "<string>",
"entity_sid": "<string>",
"resolution": "<string>",
"resolution_hint": "<string>",
"count": 123
}
],
"context": {}
},
"meta": {
"trace_id": "<string>",
"span_id": "<string>",
"timestamp": "<string>",
"duration_ms": 1,
"team_sid": "<string>",
"actor_type": "<string>"
}
}{
"success": false,
"error": {
"code": "validation_failed",
"message": "<string>",
"recoverable": true,
"suggestion": "<string>",
"field_errors": {},
"blockers": [
{
"type": "<string>",
"severity": "hard",
"description": "<string>",
"entity_sid": "<string>",
"resolution": "<string>",
"resolution_hint": "<string>",
"count": 123
}
],
"context": {}
},
"meta": {
"trace_id": "<string>",
"span_id": "<string>",
"timestamp": "<string>",
"duration_ms": 1,
"team_sid": "<string>",
"actor_type": "<string>"
}
}Authorizations
Access token issued by gtm.service.id. Its access_identity claim carries team_sid, actor_sid and actor_type, and that team scope is authoritative.
Team scope for tokens that do not carry one. Ignored when the token already names a team.
Body
application/json
Request body of send_linkedin_message.
LinkedIn account sid (ln_ac_…).
Required string length:
18Pattern:
^ln_ac_Message body; 1..8000 chars.
Required string length:
1 - 8000Existing basic-messenger thread; provide this OR a profile URN. Our sid only: a raw LinkedIn 2-…== thread id is NOT accepted here, resolve it first with search_linkedin_conversations filter.conversation_hash.eq.
Required string length:
18Pattern:
^ln_cv_Regular-profile URN (ACoAA…) for a new thread.
Maximum string length:
128Sales Navigator URN (ACwAA…); interchangeable with ln_id.
Maximum string length:
64Exactly one of file_base64 / file_url per item; 35 MB decoded total per send. An item whose file_type is video/* is delivered as a playable video in the thread; any other type arrives as a generic file attachment.
Show child attributes
Show child attributes
Your own key for this send (a task id, an idempotency token; max 255), stored as given on the row and searchable, so you can ask whether the send landed before repeating it.
Maximum string length:
255Response
action success envelope.
Available options:
true Available options:
action kebab-case verb; matches the route segment.
Show child attributes
Show child attributes
Show child attributes
Show child attributes
Show child attributes
Show child attributes