For Developers

Build on the Nexus Platform

Access Donna's AI engine through our REST API. Integrate voice queries, OLED display control, and real-time audio into your own applications.

View API Docs Join Waitlist

Python SDK JavaScript SDK REST API Webhooks BLE Protocol

What You Can Build

The Nexus API gives you full programmatic access to the pen's hardware and AI pipeline.

Custom AI Modes

Create your own Donna modes with custom system prompts, temperature settings, and response formatting tailored to your use case.

OLED Control

Push arbitrary text, icons, and animations to the pen's 128x128 OLED display over BLE in real time.

Voice Pipeline

Stream audio from the pen's I2S microphone, transcribe with Whisper, and send TTS responses back at 24kHz.

Session History

Access full conversation histories, usage analytics, and per-user AI memory through our paginated REST endpoints.

Webhooks

Subscribe to pen events — button presses, query completions, BLE connect/disconnect — and trigger workflows in your backend.

Education Tools

Build flashcard engines, quiz generators, and adaptive learning pipelines that run directly on the Nexus Pen hardware.

API Preview

Simple, Powerful API

Send a voice query and get a structured response in under 2 seconds. Our API handles transcription, AI inference, TTS synthesis, and BLE delivery automatically.

bash

curl -X POST https://api.nexuspen.org/v1/query \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "mode": "answer",
    "text": "What is photosynthesis?",
    "pen_id": "pen_abc123",
    "stream_to_oled": true
  }'

python

import nexuspen

client = nexuspen.Client(api_key="YOUR_API_KEY")

response = client.query(
    mode="answer",
    text="What is photosynthesis?",
    pen_id="pen_abc123",
    stream_to_oled=True
)

print(response.text)
print(response.audio_url)
print(response.latency_ms)

javascript

import { NexusPen } from "@nexuspen/sdk";

const client = new NexusPen({ apiKey: "YOUR_API_KEY" });

const response = await client.query({
  mode: "answer",
  text: "What is photosynthesis?",
  penId: "pen_abc123",
  streamToOled: true,
});

console.log(response.text);
console.log(response.latencyMs);

JSON Response 200 OK

{
  "id": "qry_7x9mKpL3nR",
  "mode": "answer",
  "text": "Photosynthesis is the process by
which plants convert sunlight, CO2,
and water into glucose and oxygen
using chlorophyll in their cells.",
  "audio_url": "https://cdn.nexuspen.org/
            tts/qry_7x9mKpL3nR.wav",
  "oled_delivered": true,
  "latency_ms": 1847,
  "tokens": {
    "prompt": 24,
    "completion": 52,
    "total": 76
  },
  "created_at": "2025-11-14T09:23:41Z"
}

Rate Limits

Free 50 queries / day

Plus 500 queries / day

Pro 5,000 queries / day

Enterprise Unlimited

API Access

Join the Developer Waitlist

We're granting early API access to a select group of developers. Get notified when your access is ready.

Free 500 queries during beta

Direct Slack access to our engineering team

Early access to new endpoints

API Pricing

Pay only for what you use. All plans include access to Donna's full AI pipeline.

Sandbox

Free

Perfect for prototyping and testing your integration.

50 queries / day
All 5 AI modes
REST API access
OLED streaming
Webhooks

Join Waitlist