curl --request POST \
--url https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"expected_step_id": "<string>"
}
'import requests
url = "https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain"
payload = { "expected_step_id": "<string>" }
headers = {
"Authorization": "Bearer <token>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
body: JSON.stringify({expected_step_id: '<string>'})
};
fetch('https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain', 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.harmonica.chat/api/v1/sessions/{id}/continue-chain",
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([
'expected_step_id' => '<string>'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"Content-Type: application/json"
],
]);
$response = curl_exec($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.harmonica.chat/api/v1/sessions/{id}/continue-chain"
payload := strings.NewReader("{\n \"expected_step_id\": \"<string>\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
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.harmonica.chat/api/v1/sessions/{id}/continue-chain")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"expected_step_id\": \"<string>\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"expected_step_id\": \"<string>\"\n}"
response = http.request(request)
puts response.read_body{
"chain_id": "<string>",
"from_step_id": "<string>",
"action": "advanced",
"next_step_id": "<string>",
"next_session_id": "<string>",
"actor_id": "<string>",
"auth_method": "session",
"source": "api",
"occurred_at": "2023-11-07T05:31:56Z",
"replayed": true
}{
"error": {
"code": "forbidden",
"message": "<string>",
"blockers": [
{
"code": "chain_not_active",
"message": "<string>",
"step_id": "<string>",
"session_id": "<string>"
}
]
}
}Request guarded host chain progression
Requires owner/admin access to the origin session. Platform session metadata audit keys cannot advance chains, even for a session they own. Pass current_step_id from chain-state as expected_step_id. No force, trigger override, credit-retry query option or completion bypass exists in this API-key contract. Existing empty-body browser UI/internal calls retain their legacy response contract and are not described here.
Completion/quorum/timer and role readiness use the normal runtime rules. Missing predecessor summaries return summary_required blockers without enqueueing work or changing state; generate those summaries through the existing summary API/tool, then retry with the same expected step. Rejected preconditions make no chain writes. A runtime handoff failure retains the normal runtime pause behavior and returns advance_failed.
A committed transition stores actor/transport evidence atomically. A retry of that expected step returns its original receipt with replayed=true, without creating sessions/assignments or redispatching notifications. The normal runtime may catch up additional already-complete automatic steps; inspect chain-state again for the latest frontier. Normal progression may reserve credits and email assigned roster participants.
curl --request POST \
--url https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain \
--header 'Authorization: Bearer <token>' \
--header 'Content-Type: application/json' \
--data '
{
"expected_step_id": "<string>"
}
'import requests
url = "https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain"
payload = { "expected_step_id": "<string>" }
headers = {
"Authorization": "Bearer <token>",
"Content-Type": "application/json"
}
response = requests.post(url, json=payload, headers=headers)
print(response.text)const options = {
method: 'POST',
headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
body: JSON.stringify({expected_step_id: '<string>'})
};
fetch('https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain', 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.harmonica.chat/api/v1/sessions/{id}/continue-chain",
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([
'expected_step_id' => '<string>'
]),
CURLOPT_HTTPHEADER => [
"Authorization: Bearer <token>",
"Content-Type: application/json"
],
]);
$response = curl_exec($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.harmonica.chat/api/v1/sessions/{id}/continue-chain"
payload := strings.NewReader("{\n \"expected_step_id\": \"<string>\"\n}")
req, _ := http.NewRequest("POST", url, payload)
req.Header.Add("Authorization", "Bearer <token>")
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.harmonica.chat/api/v1/sessions/{id}/continue-chain")
.header("Authorization", "Bearer <token>")
.header("Content-Type", "application/json")
.body("{\n \"expected_step_id\": \"<string>\"\n}")
.asString();require 'uri'
require 'net/http'
url = URI("https://app.harmonica.chat/api/v1/sessions/{id}/continue-chain")
http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n \"expected_step_id\": \"<string>\"\n}"
response = http.request(request)
puts response.read_body{
"chain_id": "<string>",
"from_step_id": "<string>",
"action": "advanced",
"next_step_id": "<string>",
"next_session_id": "<string>",
"actor_id": "<string>",
"auth_method": "session",
"source": "api",
"occurred_at": "2023-11-07T05:31:56Z",
"replayed": true
}{
"error": {
"code": "forbidden",
"message": "<string>",
"blockers": [
{
"code": "chain_not_active",
"message": "<string>",
"step_id": "<string>",
"session_id": "<string>"
}
]
}
}Authorizations
API key authentication. Pass your key as a Bearer token.
Keys use the format hm_live_<32 hex chars>.
Generate keys from your Harmonica dashboard settings.
Path Parameters
Body
1 - 200Response
Original or replayed committed transition receipt
advanced, closed session, api_key Original committing transport; replay preserves the original actor and source.
api, mcp