REST API · NATIVE MCP · MANUFACTURER-SOURCED
THE HVAC TROUBLESHOOTING INFRASTRUCTURE LAYER
OUR BRAIN.
YOUR TOOLS.
Two sockets — REST and MCP — to plug 400,000+ sourced error codes into your product, AI agent, or pipeline. Integrate in an afternoon. We don’t bill what we don’t know.
- Sourced answers: page, section, value — never invented
- REST + native MCP: integrate in an afternoon
- JS & Python SDKs, OpenAPI spec and MCP server included
curl https://api.askmarcel.app/v1/diagnostic \
-H "Authorization: Bearer ak_live_…" \
-d '{ "brand": "Mitsubishi", "model": "Ecodan PUHZ-W85", "error_code": "E7" }'THE REAL BOTTLENECK
YOUR SOFTWARE KNOWS WHO, WHEN, WHERE.
NOT HOW TO FIX IT.
Your CMMS manages routes. Your ERP handles billing. Your AI agent answers customers. But at the critical moment — the error code on the unit — they all send the technician back to the hotline and 400-page PDFs. The technical data is missing. Building a multi-brand HVAC troubleshooting database in-house takes years of crawling, structuring, and field verification. Or one line of code.
Building in-house = a 3-year project.
Collecting, cleaning, and structuring manuals from dozens of brands is a job in itself. Not a sprint.
Generic AI invents.
An LLM without domain data hallucinates an ohmic value. In the field, a wrong value means a return visit.
The data already exists — elsewhere.
AskMarcel has already crawled, structured, and verified it. You plug it in instead of rebuilding it.
ONE API, THREE PROMISES
MARCEL ANSWERS. YOUR TOOLS ACT.
From raw request to displayed procedure — no hallucination.
Flexible input: code, model, or photo.
Send an error code, model reference, nameplate image in base64, or a natural language question. The API identifies context and normalizes the request. Endpoint POST /v1/diagnostic.
Two sockets, one afternoon
The API doesn’t “generate”. It queries 400,000+ sourced error codes. REST or MCP: your team plugs in within an afternoon. Every answer returns its exact source — manual, page, section.
Structured output: ready to display.
Clean JSON: step-by-step procedure, expected values (ohmic, pressure, temperature), spare part reference. Display it as-is in your UI, or pass it to your agent. Ticket closed on first visit.
REST FOR YOUR SOFTWARE. MCP FOR YOUR AGENTS.
REST API
To integrate AskMarcel into an existing product.
- Endpoints: /diagnostic, /search, /error-codes, /procedure
- Bearer key auth, clear quotas, webhooks
- JS/TS and Python SDKs, OpenAPI provided
- Ideal for: CMMS, ERP, service portals, field mobile apps
MCP Server
To give any AI agent real HVAC expertise.
- Native MCP server: Claude, ChatGPT, Gemini, custom agents
- The agent "calls" Marcel as a tool, with sources
- Zero glue code: add the server, the agent can diagnose
- Ideal for: service copilots, support chatbots, internal assistants
{
"mcpServers": {
"askmarcel": {
"url": "https://mcp.askmarcel.app",
"headers": { "Authorization": "Bearer ak_live_…" }
}
}
}The same verified brain. Two ports. Choose the one that fits your stack.
DEVELOPER DOCUMENTATION
INTEGRATE IN ONE AFTERNOON.
Step-by-step guides, OpenAPI reference and platform tutorials — public and account-free.
Claude Desktop
The strongest case: remote MCP server at mcp.askmarcel.app with OAuth or API key. Claude calls diagnose and cites sources.
ChatGPT
UI form configuration in Developer Mode (no JSON to paste). Requires ChatGPT Plus/Pro/Business/Enterprise/Edu.
ElevenLabs
We do not integrate ElevenLabs. You connect your agent to our API — REST and/or MCP. No proprietary connector.
ManyChat
ManyChat does not support MCP — External Request HTTP only. Map the JSON response to display steps to the technician.
n8n / Make / Zapier
The most common adoption path: HTTP Request node to api.askmarcel.app/v1/diagnostic. Ideal for automating support workflows.
FOR DEVELOPERS & INTEGRATORS
Developers & AI agents
GIVE YOUR AGENT REAL DOMAIN EXPERTISE.
A generalist LLM guesses. Plug in the AskMarcel MCP server and your agent cites its sources: manual, page, value. Free Developer key (250 req/month), SDKs and OpenAPI ready — integrate in an afternoon.
{
"mcpServers": {
"askmarcel": {
"url": "https://mcp.askmarcel.app",
"headers": { "Authorization": "Bearer ak_live_…" }
}
}
}Decision-maker (service desk, e-commerce, publisher) rather than developer? Discover Marcel Inside (FR) →
WHY MARCEL, NOT AN LLM ALONE
Integration that doesn’t bill uncertainty
400,000+ branchable error codes
Manufacturer corpus exposed via REST and MCP — for your stack, not a marketing demo. No Wikipedia, no invention.
Sourced, always.
Page, section, value. Traceable answers, never invented.
All brands
Heat pumps, AC, boilers, stoves & pellets (Daikin, Viessmann, Mitsubishi, Palazzetti…).
11 languages in production
Multi-market rollout without rebuilding.
0+
diagnostics
0
languages
0
HVAC families
0
access modes
ONE PLUG FOR EVERY SCALE
PLUG IN. NO SURPRISE INVOICE.
Developer to test. Starter and Business activate self-serve: you're not buying volume, you're buying the right to build on it. White-label with the team.
We only bill what we know
A request is only counted when the answer is sourced and usable. Errors and empty responses are free.
Developer
Testing, POC, personal agents
- 250 requests/month — hard cap
- REST API + MCP server
- “Powered by AskMarcel” attribution
- Testing and POC — production not permitted
Starter
Indies, integrators
- Production use permitted
- REST + MCP, no attribution
- Webhooks & email support
- 1,000 requests/month included
Business
Service companies, CMMS/ERP vendors
- Contractual SLA & high rate limits
- Citable source — manual + page
- Priority support · unlimited seats
- Fair use: 7,500 requests/month
Scale / White-label
Manufacturers, distributors, large vendors
- Dedicated volume
- White-label
- Custom corpus
- Account manager
- Overage: one single pack, €29 per 1,000 requests. Prepaid, no expiration, never billed in arrears.
- 2 months free when paid annually upfront: Starter €290/year, Business €1,490/year.
- Developer: 250 requests/month, hard cap, no top-up. Built to test, not to ship.
- A single avoided site revisit (€150+) pays for a year of Starter.
Frequently asked questions
Everything you need to know before plugging in Marcel.
Need technical help? Contact our team
THE BRAIN IS READY. PLUG IT IN.
Create a free key in 2 minutes, or talk to the team for fleet / white-label setup.