Create session

curl --request POST \
  --url https://app.harmonica.chat/api/v1/sessions \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "topic": "<string>",
  "goal": "<string>",
  "context": "<string>",
  "critical": "<string>",
  "prompt": "<string>",
  "template_id": "<string>",
  "project_id": "<string>",
  "roster": [
    {
      "email": "jsmith@example.com",
      "displayName": "<string>",
      "auth0Sub": "<string>",
      "rolesByStep": {}
    }
  ],
  "questions": [
    {
      "text": "<string>"
    }
  ],
  "cross_pollination": false,
  "widgets_enabled": false,
  "results_visibility": "host",
  "distribution": [
    {
      "channel": "telegram",
      "group_id": "<string>"
    }
  ]
}
'

import requests

url = "https://app.harmonica.chat/api/v1/sessions"

payload = {
    "topic": "<string>",
    "goal": "<string>",
    "context": "<string>",
    "critical": "<string>",
    "prompt": "<string>",
    "template_id": "<string>",
    "project_id": "<string>",
    "roster": [
        {
            "email": "jsmith@example.com",
            "displayName": "<string>",
            "auth0Sub": "<string>",
            "rolesByStep": {}
        }
    ],
    "questions": [{ "text": "<string>" }],
    "cross_pollination": False,
    "widgets_enabled": False,
    "results_visibility": "host",
    "distribution": [
        {
            "channel": "telegram",
            "group_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({
    topic: '<string>',
    goal: '<string>',
    context: '<string>',
    critical: '<string>',
    prompt: '<string>',
    template_id: '<string>',
    project_id: '<string>',
    roster: [
      {
        email: 'jsmith@example.com',
        displayName: '<string>',
        auth0Sub: '<string>',
        rolesByStep: {}
      }
    ],
    questions: [{text: '<string>'}],
    cross_pollination: false,
    widgets_enabled: false,
    results_visibility: 'host',
    distribution: [{channel: 'telegram', group_id: '<string>'}]
  })
};

fetch('https://app.harmonica.chat/api/v1/sessions', 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",
  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([
    'topic' => '<string>',
    'goal' => '<string>',
    'context' => '<string>',
    'critical' => '<string>',
    'prompt' => '<string>',
    'template_id' => '<string>',
    'project_id' => '<string>',
    'roster' => [
        [
                'email' => 'jsmith@example.com',
                'displayName' => '<string>',
                'auth0Sub' => '<string>',
                'rolesByStep' => [
                                
                ]
        ]
    ],
    'questions' => [
        [
                'text' => '<string>'
        ]
    ],
    'cross_pollination' => false,
    'widgets_enabled' => false,
    'results_visibility' => 'host',
    'distribution' => [
        [
                'channel' => 'telegram',
                'group_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"

	payload := strings.NewReader("{\n  \"topic\": \"<string>\",\n  \"goal\": \"<string>\",\n  \"context\": \"<string>\",\n  \"critical\": \"<string>\",\n  \"prompt\": \"<string>\",\n  \"template_id\": \"<string>\",\n  \"project_id\": \"<string>\",\n  \"roster\": [\n    {\n      \"email\": \"jsmith@example.com\",\n      \"displayName\": \"<string>\",\n      \"auth0Sub\": \"<string>\",\n      \"rolesByStep\": {}\n    }\n  ],\n  \"questions\": [\n    {\n      \"text\": \"<string>\"\n    }\n  ],\n  \"cross_pollination\": false,\n  \"widgets_enabled\": false,\n  \"results_visibility\": \"host\",\n  \"distribution\": [\n    {\n      \"channel\": \"telegram\",\n      \"group_id\": \"<string>\"\n    }\n  ]\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")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"topic\": \"<string>\",\n  \"goal\": \"<string>\",\n  \"context\": \"<string>\",\n  \"critical\": \"<string>\",\n  \"prompt\": \"<string>\",\n  \"template_id\": \"<string>\",\n  \"project_id\": \"<string>\",\n  \"roster\": [\n    {\n      \"email\": \"jsmith@example.com\",\n      \"displayName\": \"<string>\",\n      \"auth0Sub\": \"<string>\",\n      \"rolesByStep\": {}\n    }\n  ],\n  \"questions\": [\n    {\n      \"text\": \"<string>\"\n    }\n  ],\n  \"cross_pollination\": false,\n  \"widgets_enabled\": false,\n  \"results_visibility\": \"host\",\n  \"distribution\": [\n    {\n      \"channel\": \"telegram\",\n      \"group_id\": \"<string>\"\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://app.harmonica.chat/api/v1/sessions")

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  \"topic\": \"<string>\",\n  \"goal\": \"<string>\",\n  \"context\": \"<string>\",\n  \"critical\": \"<string>\",\n  \"prompt\": \"<string>\",\n  \"template_id\": \"<string>\",\n  \"project_id\": \"<string>\",\n  \"roster\": [\n    {\n      \"email\": \"jsmith@example.com\",\n      \"displayName\": \"<string>\",\n      \"auth0Sub\": \"<string>\",\n      \"rolesByStep\": {}\n    }\n  ],\n  \"questions\": [\n    {\n      \"text\": \"<string>\"\n    }\n  ],\n  \"cross_pollination\": false,\n  \"widgets_enabled\": false,\n  \"results_visibility\": \"host\",\n  \"distribution\": [\n    {\n      \"channel\": \"telegram\",\n      \"group_id\": \"<string>\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "topic": "<string>",
  "goal": "<string>",
  "status": "active",
  "participant_count": 123,
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z",
  "join_url": "<string>",
  "chain": {
    "status": "started",
    "chainInstanceId": "<string>",
    "stepId": "<string>",
    "message": "<string>",
    "reason": "<string>"
  }
}

{
  "error": {
    "code": "validation_error",
    "message": "topic is required"
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid or missing API key"
  }
}

POST

sessions

Create session

curl --request POST \
  --url https://app.harmonica.chat/api/v1/sessions \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "topic": "<string>",
  "goal": "<string>",
  "context": "<string>",
  "critical": "<string>",
  "prompt": "<string>",
  "template_id": "<string>",
  "project_id": "<string>",
  "roster": [
    {
      "email": "jsmith@example.com",
      "displayName": "<string>",
      "auth0Sub": "<string>",
      "rolesByStep": {}
    }
  ],
  "questions": [
    {
      "text": "<string>"
    }
  ],
  "cross_pollination": false,
  "widgets_enabled": false,
  "results_visibility": "host",
  "distribution": [
    {
      "channel": "telegram",
      "group_id": "<string>"
    }
  ]
}
'

import requests

url = "https://app.harmonica.chat/api/v1/sessions"

payload = {
    "topic": "<string>",
    "goal": "<string>",
    "context": "<string>",
    "critical": "<string>",
    "prompt": "<string>",
    "template_id": "<string>",
    "project_id": "<string>",
    "roster": [
        {
            "email": "jsmith@example.com",
            "displayName": "<string>",
            "auth0Sub": "<string>",
            "rolesByStep": {}
        }
    ],
    "questions": [{ "text": "<string>" }],
    "cross_pollination": False,
    "widgets_enabled": False,
    "results_visibility": "host",
    "distribution": [
        {
            "channel": "telegram",
            "group_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({
    topic: '<string>',
    goal: '<string>',
    context: '<string>',
    critical: '<string>',
    prompt: '<string>',
    template_id: '<string>',
    project_id: '<string>',
    roster: [
      {
        email: 'jsmith@example.com',
        displayName: '<string>',
        auth0Sub: '<string>',
        rolesByStep: {}
      }
    ],
    questions: [{text: '<string>'}],
    cross_pollination: false,
    widgets_enabled: false,
    results_visibility: 'host',
    distribution: [{channel: 'telegram', group_id: '<string>'}]
  })
};

fetch('https://app.harmonica.chat/api/v1/sessions', 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",
  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([
    'topic' => '<string>',
    'goal' => '<string>',
    'context' => '<string>',
    'critical' => '<string>',
    'prompt' => '<string>',
    'template_id' => '<string>',
    'project_id' => '<string>',
    'roster' => [
        [
                'email' => 'jsmith@example.com',
                'displayName' => '<string>',
                'auth0Sub' => '<string>',
                'rolesByStep' => [
                                
                ]
        ]
    ],
    'questions' => [
        [
                'text' => '<string>'
        ]
    ],
    'cross_pollination' => false,
    'widgets_enabled' => false,
    'results_visibility' => 'host',
    'distribution' => [
        [
                'channel' => 'telegram',
                'group_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"

	payload := strings.NewReader("{\n  \"topic\": \"<string>\",\n  \"goal\": \"<string>\",\n  \"context\": \"<string>\",\n  \"critical\": \"<string>\",\n  \"prompt\": \"<string>\",\n  \"template_id\": \"<string>\",\n  \"project_id\": \"<string>\",\n  \"roster\": [\n    {\n      \"email\": \"jsmith@example.com\",\n      \"displayName\": \"<string>\",\n      \"auth0Sub\": \"<string>\",\n      \"rolesByStep\": {}\n    }\n  ],\n  \"questions\": [\n    {\n      \"text\": \"<string>\"\n    }\n  ],\n  \"cross_pollination\": false,\n  \"widgets_enabled\": false,\n  \"results_visibility\": \"host\",\n  \"distribution\": [\n    {\n      \"channel\": \"telegram\",\n      \"group_id\": \"<string>\"\n    }\n  ]\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")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"topic\": \"<string>\",\n  \"goal\": \"<string>\",\n  \"context\": \"<string>\",\n  \"critical\": \"<string>\",\n  \"prompt\": \"<string>\",\n  \"template_id\": \"<string>\",\n  \"project_id\": \"<string>\",\n  \"roster\": [\n    {\n      \"email\": \"jsmith@example.com\",\n      \"displayName\": \"<string>\",\n      \"auth0Sub\": \"<string>\",\n      \"rolesByStep\": {}\n    }\n  ],\n  \"questions\": [\n    {\n      \"text\": \"<string>\"\n    }\n  ],\n  \"cross_pollination\": false,\n  \"widgets_enabled\": false,\n  \"results_visibility\": \"host\",\n  \"distribution\": [\n    {\n      \"channel\": \"telegram\",\n      \"group_id\": \"<string>\"\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://app.harmonica.chat/api/v1/sessions")

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  \"topic\": \"<string>\",\n  \"goal\": \"<string>\",\n  \"context\": \"<string>\",\n  \"critical\": \"<string>\",\n  \"prompt\": \"<string>\",\n  \"template_id\": \"<string>\",\n  \"project_id\": \"<string>\",\n  \"roster\": [\n    {\n      \"email\": \"jsmith@example.com\",\n      \"displayName\": \"<string>\",\n      \"auth0Sub\": \"<string>\",\n      \"rolesByStep\": {}\n    }\n  ],\n  \"questions\": [\n    {\n      \"text\": \"<string>\"\n    }\n  ],\n  \"cross_pollination\": false,\n  \"widgets_enabled\": false,\n  \"results_visibility\": \"host\",\n  \"distribution\": [\n    {\n      \"channel\": \"telegram\",\n      \"group_id\": \"<string>\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "topic": "<string>",
  "goal": "<string>",
  "status": "active",
  "participant_count": 123,
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z",
  "join_url": "<string>",
  "chain": {
    "status": "started",
    "chainInstanceId": "<string>",
    "stepId": "<string>",
    "message": "<string>",
    "reason": "<string>"
  }
}

{
  "error": {
    "code": "validation_error",
    "message": "topic is required"
  }
}

{
  "error": {
    "code": "unauthorized",
    "message": "Invalid or missing API key"
  }
}

Authorizations

Authorization

string

header

required

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.

Body

application/json

Request body for creating a new session.

topic

string

required

Session topic / title

goal

string

required

What the session aims to achieve

context

string

Background context for participants (e.g. SESSION.md from a prior session)

critical

string

Critical question or constraint

prompt

string

Custom facilitation prompt. If omitted, a prompt is auto-generated server-side from the topic, goal, context, and critical fields. Falls back to a basic facilitation prompt if generation fails.

template_id

string

ID of a template to use

project_id

string

Attach the new session to a project (workspace) at create time. Requires editor access to the project.

roster

object[]

HAR-1582 - participants for a chain template's first step. Only meaningful when template_id resolves to a chain template; ignored otherwise.

Four of the live chain templates declare roles and an assignment strategy (Delphi panel, Governance Meeting, Many-to-Many Readiness, Example Mapping) and cannot bootstrap without a roster; for those, omitting it returns chain.status "roster_incomplete" on an otherwise successful create. The other seven declare no roles and start with an empty roster.

Show child attributes

questions

object[]

Pre-session questions shown to participants before facilitation begins

Show child attributes

cross_pollination

boolean

default:false

Enable cross-pollination of ideas between participant threads

widgets_enabled

boolean

default:false

Enable AI-emitted Polls and ratings widgets (SingleSelect, MultiSelect, RatingScale, RankingList) during the session. When true, the facilitator may call widget tools mid-conversation to present interactive inputs instead of plain text questions.

results_visibility

enum<string>

default:host

Who can see aggregated session results.

host (default) — only the session owner can see results.
participants — anyone who completed the session can see what others said (drives the end-of-chat "See what others said" link).
public — anyone with the session URL can see results without participating. MCP / harmonica-chat callers typically pass participants since programmatic and Telegram-distributed sessions usually want distributed visibility.

Available options:

public,

participants,

host

distribution

object[]

Distribution channels for the session (e.g. Telegram groups)

Show child attributes

Response

Session created

Session object returned after creation. Extends SessionListItem with a join URL.

string<uuid>

required

topic

string

required

goal

string

required

status

enum<string>

required

Available options:

active

participant_count

integer

required

created_at

string<date-time>

required

updated_at

string<date-time>

required

join_url

string<uri>

required

Direct URL for participants to join the session

chain

object

Outcome of chain bootstrap. Present only when template_id named a chain template. Any status other than started or resumed means the session was created and is real but is NOT running as a chain, so treat this field as the authoritative signal rather than assuming a 201 implies a running chain. The most common degraded status is roster_incomplete, because several chain templates declare roles and cannot start without a roster.

Show child attributes

Overview

Endpoints

Integrations

Create session

Authorizations

Body

Response