THEO FOR DEVELOPERS

Ship AI in three lines.

One API. Every model. Streaming, skills, tools, memory, webhooks, and open-source adapters for Telegram and WhatsApp. All the plumbing. None of the mess.

1API key
10+Engines
3Channels
Use cases

THREE LINES TO SHIP

npm install @hitheo/sdk - then pick your use case.

OPEN SOURCE · TYPESCRIPT · FULL DOCS

DOCS: SDK REFERENCE →
your-app.ts
import { Theo } from "@hitheo/sdk";

const theo = new Theo({ apiKey: "theo_sk_..." });

const res = await theo.complete({
  prompt: "Explain quantum computing simply",
  mode: "auto",  // → routes to Theo Flash (quick chat)
});

console.log(res.text);
console.log(res.model);       // "theo-1-flash"
console.log(res.cost);        // "$0.0003"
TypeScriptStreamingTree-shakeable0 dependencies

WORKS EVERYWHERE

Same brain, same memory, same skills. Every channel. Open-source adapters.

TelegramWhatsAppREST API

BRING YOUR STACK

Next.jsExpressVercelCloudflare WorkersAWS LambdaSupabaseBunDenoNode.js

HOW IT WORKS

Every request flows through six stages. Your prompt in, the perfect engine out, automatically.

CLICK ANY STEP TO LEARN MORE

DOCS: ORCHESTRATION PIPELINE →

INTELLIGENT ROUTING

The right model for every message. Every time. Automatically.

Click any model to explore

Docs: Engine Routing →

WHY theo'S ROUTING IS DIFFERENT

Understands intent

Theo reads every prompt and picks the right engine in the background. No keywords, no configuration, no routing tables to maintain.

Pays attention to cost

Simple questions use fast, cheap models. Complex reasoning gets the premium ones. You save on every routine request, automatically.

Snappy by default

Most prompts classify in milliseconds. Quick answers feel instant. Long-running tasks stream so users never wonder if it froze.

Built-in failover

If one provider hiccups, Theo slides to the next. Your widget, your app, and your automations keep working. Your users never notice.

HOW theo PERFORMSSample

Example performance profile for each routing mode. Live numbers replace these automatically once telemetry accumulates.

Theo Flash
420ms
Theo Code
1850ms
Theo Reason
2400ms
Theo Create
3800ms
Theo Research
4200ms
Theo Motion
18000ms
Based on internal testing across 580 sample requests. See full methodology
EXECUTABLE VISUAL INTELLIGENCE

WATCH IT EXECUTE

Type a prompt and watch theo decompose it into a multi-model execution chain, routed and run in real time.

TRY A MULTI-MODEL PRESET OR TYPE YOUR OWN

quickstart.ts
// The same routing happens whether you call it from your app,
// embed the widget, or type in the playground.

theo.ask({
  prompt: "Build me a video about a dog on a skateboard and roast me about it",
  mode: "auto",
});

// → Theo Code (auto)
EXECUTABLE VISUAL INTELLIGENCE

BUILD AN E.V.I.

Your persona. Your skills. theo's engine under the hood.

DOCS: PERSONAS & E.V.I. →
Your Persona

Replace Theo's personality with your own brand. Your users never see Theo. They see your AI.

Your Skills + Tools

Install marketplace skills for domain expertise. Pass inline tools for your product's actions.

Visual Canvas

Drag-and-drop skill builder. Connect prompts, models, tools, vision nodes. Compile, test, and publish.

theo's Engine

Multi-model routing, intent classification, agent loop, memory, billing, caching: all handled.

BEFORE AFTER

WITHOUT THEO (40+ lines)
const model = pickModel(prompt);
const tools = resolveTools(user);
const system = buildPrompt(persona, skills);
const res = await llmProvider.complete({ model, ... });
const toolResults = await executeTools(res);
const final = await llmProvider.complete({ ... });
await debitCredits(user, res.usage);
await logAudit(user, res);
WITH THEO E.V.I. (5 lines)
import { Theo } from "@hitheo/sdk";

const theo = new Theo({ apiKey: process.env.THEO_KEY });

const evi = theo.evi({
  persona: "You are Eva, AcmeCorp's AI...",
  skills: ["insurance-quoting"],
  tools: [lookupCustomer, updatePolicy],
});

const res = await evi.complete({ prompt: "..." });

ONE API CALL. EVERYTHING HANDLED.

Intent classification. Model routing. Skill injection. Tool execution. Memory. Streaming. Billing. Audit. Caching. All from evi.complete().

SKILL STORE

An app store for AI capabilities. Install domain skills that give Theo specialized knowledge - or build and publish your own.

BROWSE · INSTALL · PUBLISH

api.hitheo.ai/skills
AllOfficialCommunity
Insurance
Insurance Quoting
by hitheo

Compare rates across 5+ carriers in real-time. Pre-built data connectors, carrier-specific rate tables, and compliance guardrails.

1.2k
Developer
Code Review
by hitheo

Analyze PRs for security vulnerabilities, performance issues, and architecture anti-patterns. GitHub, GitLab, Bitbucket.

3.4k
Research
Deep Research
by hitheo

Multi-step web research with source synthesis. Crawl, read, and produce cited reports, not just summaries.

2.8k
Data
Data Extraction
by community

OCR + structured extraction from PDFs, images, and scanned documents. Returns typed JSON, not raw text.

890
Content
Content Writer
by community

Blog posts, emails, social copy. Adapts tone to your brand voice. SEO optimization built-in.

1.6k
Custom
Custom Skill
by you

Build via code or the visual Canvas. Publish privately, to your org, or to the public marketplace.

-

BUILD YOUR OWN

my-skill.ts
import { defineSkill } from "@hitheo/sdk";

export default defineSkill({
  name: "inventory-check",
  tools: [checkStock, reorderAlert],
  knowledge: ["./catalog/*.json"],
});

// npx theo publish
E.V.I. CANVAS

Drag-and-drop visual builder. Connect prompts, models, tools, and vision nodes. No code required.

OPEN CANVAS →

PUBLISH YOUR WAY

Publish privately (just you), to your organization (team-only), or to the public marketplace. Earn credits for every API call that activates your skill.

DEVELOPER DASHBOARD

One dashboard for everything. Keys, usage, logs, routing config. No more switching between 4 provider consoles.

api.hitheo.ai/dashboard
0
Requests today
0ms
Avg latency
$0.21
Cost today
0
Models used
REQUEST VOLUME (24H)
LIVE REQUESTS
15:42:03Flashfast$0.001 · 120ms
15:42:01Codecode$0.042 · 1.2s
15:41:58Createimage$0.008 · 3.4s
API Keys
Create, rotate, and scope keys per environment
Usage Analytics
Per-model cost, latency, and volume breakdowns
Real-time Logs
Stream every request: model, mode, cost, duration
Routing Config
Override defaults, pin models, set cost caps

WORKS EVERYWHERE

Channel-agnostic core. Open-source adapters for Telegram and WhatsApp forward webhook updates into Theo; pass the same conversation_id to share memory across channels.

DOCS: CHANNEL GUIDES →
THEO BRAINSAME ORCHESTRATION · EVERYWHERE
WEB APP
TELEGRAM
WHATSAPP
REST API
CUSTOM
Telegram
@hitheo/telegram
User: What's the weather?
theo: Quick one. Fast mode. ⚡
WhatsApp
@hitheo/whatsapp
User: Build me a landing page
theo: Code mode. Warming up. 💻
REST API
@hitheo/sdk
User: POST /v1/completions
theo: Your backend, your rules. Full control.

WHAT SHIPS TODAY

FIRST-PARTY
  • Telegram adapter — @hitheo/telegram
  • WhatsApp Cloud adapter — @hitheo/whatsapp
  • REST API — @hitheo/sdk
  • Embeddable chat widget (iframe)
BRING YOUR OWN
  • Slack — via the slack-messenger skill or incoming webhook
  • Discord — custom adapter against our REST API
  • SMS / Email — custom adapter or workflow step
  • Any other channel — a thin webhook handler + theo.complete

BRING YOUR STACK

Next.jsExpressFastifyVercelCloudflare WorkersAWS LambdaSupabaseBunDenoNode.js
REAL-TIME EVENTS

Real-time events. Anywhere you work.

Every action in Theo fires a signed event. Route it to Slack, email, your CRM, or any of 5,000+ apps — without writing a backend.

Stream every completion with mode, tokens, and cost into your warehouse.

EVENTSomething happens
FILTERMatch your subscriptions
SIGNHMAC-SHA256
DELIVERPOST + retries
Slack / Discord
channel pings
Email alert
team inbox
Zapier / n8n / Make
5,000+ apps
delivered
Your server
signed webhook
delivered
signed payload
Theo-Webhook-Signature: v1=…
{
  "event": "completion.created",
  "mode": "fast",
  "tokens": 340,
  "costCents": 2
}
HMAC-SHA256 signedSSRF-guardedExponential retryReplay-safe timestamps
OPENAI-COMPATIBLE

Drop-in compatible. One-line swap.

Already shipping with the OpenAI SDK? Point baseURL atapi.hitheo.aiand you're on Theo. Auto-routing, multi-model, same API.

app.ts
import OpenAI from "openai";

const theo = new OpenAI({
  apiKey: process.env.THEO_API_KEY,
  baseURL: "https://api.hitheo.ai/v1",
});

const res = await theo.chat.completions.create({
  model: "theo-1-auto",
  messages: [{ role: "user", content: "Write me a haiku about Miami" }],
  stream: true,
});

Built for real production.

Not a toy. Not a wrapper. Theo is the same infra our own apps run on.

Streaming SSE + OpenAI chunks

Token-level streaming with tool events, artifacts, and follow-ups. Also speaks the OpenAI chat.completion format natively.

Agentic loop & tools

Skills declare their tools in a manifest. Theo plans, calls, observes, and retries with full audit trails.

Webhooks & idempotency

HMAC-signed deliveries with automatic retries, dead-letter queue, and idempotency keys for safe replays.

Provider failover

Circuit-breaker across OpenRouter, Anthropic, Gemini, and Venice. Users never notice an outage.

Memory & conversations

Pass a conversation_id and every channel (web, Telegram, WhatsApp) shares the same memory.

Credits & cost control

Per-token passthrough with unified billing. Daily caps, per-key attribution, and soft/hard limits.

PRICING

PAY AS YOU GO

Add funds. Use the API. Simple.

Add dollars to your balance and draw down per token. Passthrough model costs plus a small platform fee. No plans. No subscriptions. No commitments.

CREATE ACCOUNT
1. SIGN UP
Create a free account
Get your API key instantly
$50 free credits to start
2. ADD FUNDS
Add any amount ($5 minimum)
Secure checkout via Polar
Balance tops up instantly
3. BUILD
Every engine included
Per-token billing
Full usage dashboard

Billing by OpenCharts Inc., the company behind Theo.

READY TO BUILD?

One API key. Ten intelligent engines. Automatic routing. Conversations & memory. Extensible skills. Open-source SDK.

Start free in 30 seconds. No credit card. Your users get better answers. You write less code.