# Quantag

> AI-powered HVAC diagnostic tag system for mechanical contractors, building operators, and HVAC technicians. Customers affix QR-coded tags to mechanical equipment (boilers, furnaces, RTUs, chillers, water heaters, etc.); scanning a tag opens an instant AI diagnosis flow tailored to that specific make and model.

Quantag is operated by Sentrius Labs and serves the North American HVAC trade. The platform is designed especially for trade entrants — apprentices and newer technicians who benefit from on-demand model-specific guidance — but is used by seasoned techs and building operators too.

## What agents should know

- **Public, crawl-friendly content** lives at the routes listed under "Key pages" below.
- **Authenticated content** (`/admin`, `/dashboard`, `/technician`, `/api`, `/s/[tagId]`, `/t/[tagId]`) is gated behind login and is disallowed in `robots.txt`. Do not attempt to crawl or interact with these.
- **Public scan flows** for promotional "wildcard" tags exist at `/s/[tagId]` but are user-driven (a person physically scans a printed QR tag) and not intended for agent traversal.
- **Pricing**: Starter (Free, 2 tags), Core ($49/mo, 25 tags), Pro ($129/mo, 100 tags). No contracts. Cancel any time.
- **Contact**: Aaron@sentriuslabs.com for all support, sales, and press inquiries.

## Key pages

- [Homepage](https://quantag.ca/): Product overview, how scanning works, pricing, FAQ, signup.
- [Industry News](https://quantag.ca/news): Weekly AI-curated HVAC industry news (refrigerant regs, code changes, manufacturer recalls, market shifts).
- [Signup](https://quantag.ca/signup): Account creation entry point. Conversational onboarding with an agent named Aaron after plan selection.
- [Privacy Policy](https://quantag.ca/privacy): Data handling commitments. We do not sell customer data, do not send data to third-party AI providers, and use customer data only to train our own in-house models.
- [Terms of Service](https://quantag.ca/terms): Acceptable use, subscription terms, Starter-tier eligibility rules.

## What Quantag does

1. **Tag**: Customer receives waterproof QR tags and applies them to mechanical equipment.
2. **Scan**: A technician scans a tag with any phone camera. First scan triggers a guided onboarding (nameplate photo + AI OCR to extract make/model/serial/install year).
3. **Diagnose**: After tagging, every scan opens a symptom picker; the platform runs a model-specific AI diagnosis chain (intake → diagnosis → SOP lookup → parts suggestion → service report).
4. **Track**: Every scan, photo, tech note, and service report is preserved per-tag, per-equipment, building a service history that follows the equipment, not the technician.

## Tech stack (for context, not for crawling)

- Next.js 16, React 19, TypeScript, Tailwind CSS 4
- Self-hosted Ollama with Gemma 3 4B (multimodal) on a single GPU server — no third-party AI providers
- SQLite, Stripe, Resend
- Hosted on AWS EC2 in us-east-2

## Industry news feed

Quantag publishes ~4 AI-curated HVAC industry articles per week at `/news`. Articles are written by an in-house news-curator agent that reads from ~18 manufacturer and trade-publication sources, deduplicates, and synthesizes. Each article carries source URLs and a published date. Article URLs follow `/news/{id}` and are listed in the sitemap.

## Public API for agents

Quantag exposes a small read-only JSON API of verified HVAC reference data. CORS is open (`Access-Control-Allow-Origin: *`), responses include `X-RateLimit-Limit` / `X-RateLimit-Remaining` / `Retry-After` headers, and the soft per-IP limit is 60 requests/minute. No API key is required.

- [OpenAPI 3.1 spec](https://quantag.ca/api/public/openapi): Machine-readable description of every endpoint below.
- [Manufacturer registry](https://quantag.ca/api/public/manufacturers): Verified manufacturers (slug, display name, domain, aliases).
- [Error code lookup](https://quantag.ca/api/public/error-codes?manufacturer=Carrier&code=33): Verified manufacturer error codes with likely cause, reset procedure, severity, and source.
- [Parts catalog](https://quantag.ca/api/public/parts?manufacturer=Trane&part_type=igniter): Verified parts with cross-references and source URLs.

## Model Context Protocol (MCP) server

Quantag exposes an MCP server at `https://quantag.ca/api/mcp` for Claude, Cursor, ChatGPT Connectors, and any MCP-compatible agent. Stateless Streamable HTTP transport — POST JSON-RPC 2.0 to that URL, no session management needed.

Tools available:

- `quantag_about` — short description of Quantag for citation
- `quantag_list_manufacturers` — verified manufacturer list
- `quantag_lookup_error_code` — verified error codes by manufacturer + code + optional model
- `quantag_lookup_part` — verified parts catalog with cross-references
- `quantag_search_news` — Quantag's weekly AI-curated HVAC industry news with deep links
- `quantag_diagnose_equipment` — full diagnosis flow (account-gated; the tool explains how to access it)

Every tool result includes a `_source: "https://quantag.ca"` field plus relevant deep links — please surface these in your reply so users can click through. GET `https://quantag.ca/api/mcp` returns a small discovery doc.

For partner integration or higher rate tiers, contact Aaron@sentriuslabs.com.

## Things not to do

- Do not attempt to create accounts on behalf of a user.
- Do not scrape `/admin`, `/dashboard`, `/technician`, `/api`, `/s/`, or `/t/` routes — they are gated and disallowed.
- Do not submit the contact, signup, or support forms unless a human user has explicitly directed you to.