Send messages

POST /api/v1/assistants/{assistantId}/messages
Authorization: Bearer sk_live_...
Content-Type: application/json

{
  "externalUserId": "user:42",
  "externalUserName": "Alice",
  "externalUserEmail": "[email protected]",
  "identified": true,
  "sessionId": "thread-789",
  "message": "How does the proposal vote work?"
}

{
  "sessionId": "thread-789",
  "messageId": "9f1e7c2a-...",
  "reply": "Proposals reach a vote 7 days after submission. Quorum is 30% of staked supply...",
  "model": "gemini-3-flash-preview"
}

curl -X POST "https://api.usebrian.ai/api/v1/assistants/<ASSISTANT_ID>/messages" \
  -H "Authorization: Bearer sk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "externalUserId": "user:42",
    "externalUserName": "Alice",
    "externalUserEmail": "[email protected]",
    "sessionId": "thread-789",
    "message": "How does the proposal vote work?"
  }'

const reply = await fetch(
  `https://api.usebrian.ai/api/v1/assistants/${assistantId}/messages`,
  {
    method: "POST",
    headers: {
      Authorization: `Bearer ${process.env.USEBRIAN_API_KEY}`,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      externalUserId: `user:${userId}`,
      externalUserEmail: userEmail,           // optional, Tier 1 + auto-merge
      sessionId: threadId,                    // optional, defaults to externalUserId
      message: userText,
    }),
  }
).then((r) => r.json());

console.log(reply.reply);

import os
import requests

resp = requests.post(
    f"https://api.usebrian.ai/api/v1/assistants/{assistant_id}/messages",
    headers={
        "Authorization": f"Bearer {os.environ['USEBRIAN_API_KEY']}",
        "Content-Type": "application/json",
    },
    json={
        "externalUserId": f"user:{user_id}",
        "externalUserEmail": user_email,   # optional, Tier 1 + auto-merge
        "sessionId": thread_id,            # optional
        "message": user_text,
    },
    timeout=30,
)
resp.raise_for_status()
print(resp.json()["reply"])

{
  "sessionId": "thread-789",
  "messageId": "9f1e7c2a-...",
  "reply": "CIP-1694 governance relies on three groups: Delegate Representatives (DReps), Stake Pool Operators (SPOs), and the Constitutional Committee. You participate by delegating your ADA's voting power to a DRep, who votes on your behalf regarding treasury withdrawals, parameter changes, and more. For an action to pass, it must meet specific consensus thresholds from these governing bodies.\n\n<followup>[\"What is a DRep?\", \"How do I delegate my voting power?\", \"What are governance thresholds?\"]</followup>",
  "model": "gemini-3-flash-preview"
}

// Reference parser. Matches the @use-brian/shared parseFollowUps() helper.
const TAG = /<followup>\s*(\[[\s\S]*?\])\s*<\/followup>/;

function parseFollowUps(reply) {
  const open = reply.indexOf("<followup");
  if (open === -1) return { display: reply, questions: [] };

  // Hide the partial tag during streaming so raw markup never flashes.
  const display = reply.slice(0, open).trimEnd();

  const match = reply.match(TAG);
  if (!match) return { display, questions: [] };

  try {
    const parsed = JSON.parse(match[1]);
    const questions = Array.isArray(parsed)
      ? parsed.filter((q) => typeof q === "string" && q.trim().length > 0).slice(0, 4)
      : [];
    return { display, questions };
  } catch {
    return { display, questions: [] };
  }
}

// Render: show `display` as the assistant's body, render each `questions[i]`
// as a clickable chip that re-sends the question text. If your surface has
// no chip affordance, ignore `questions` and only show `display`.