An MCP server that exposes SAP Business One as tools for any LLM. With the permissions each user already has in SAP. Self-hosted.
Not another chatbot bolted to your ERP. An open protocol that lets any agent operate SAP B1 safely — auditable tools, role-based scoping, and transactional rollback included.
Free 2-week pilot · No commitment · Response in <48h
"What I like most is how boring it is. It does what it says, doesn't hallucinate joins."— P., Solutions Architect · SAP B1 Partner
Model Context Protocol is the standard Anthropic published in 2024, now governed by the Linux Foundation. While corporate SAP still debates its gateway, we deliver the practical implementation for Business One your team can install on Monday.
Three principles. Non-negotiable.
MCP One never has more permissions than the user invoking it. Authorization lives in B1, not in a parallel YAML. If the user can't approve invoices in SAP, their agent can't either.
We expose typed business operations — create_sales_order, check_stock — not raw table access. The LLM doesn't invent joins; it executes domain verbs.
Every invocation is logged with the original prompt, the tool chosen, arguments and result. Standard OpenTelemetry log exportable to your observability stack.
Four steps. No magic, no black box. The user speaks, the LLM picks the tool, MCP One executes against Service Layer with their token, returns structured data.
"Make me an order for 12 units of SKU‑4421 for Mora Industries, 60-day payment terms."
MCP One publishes its catalog: create_sales_order, find_business_partner, check_credit_limit… The model plans.
OAuth 2.1 + PKCE. The token carries the human user's identity. Service Layer applies permissions, Transaction Notifications validate, MCP One routes.
The LLM receives the created DocEntry, the available credit limit, and the tax status. Responds in natural language — or executes the next step.
Eight modules. Zero coupling. Activate what you need — the rest doesn't consume memory, doesn't pollute the LLM's tool catalog, doesn't add attack surface.
From quotation to invoice without opening SAP. Credit limit validation, payment terms per customer and automatic holds. Idempotency with requestId so the LLM doesn't duplicate.
The agent checks projected stock, lead times and preferred supplier; proposes a purchase order; the responsible confirms with a sentence. MRP-light without migrating your real MRP.
Multi-warehouse reads consistent with the open transaction. Native batch and serial number traceability. Suitable for pharma, food and automotive environments.
General ledger, accounts receivable/payable, bank reconciliation. Agentic reporting: the LLM builds the query, MCP One executes it as a stored proc, returns typed rows.
The agent logs the call, creates the opportunity and links to the partner — all from the meeting transcript. Optional connector for 3CX PBX.
Short token, long refresh, scopes mapped 1:1 to B1 authorizations. No credentials in the clear in the agent. Granular audit by user, tool and argument.
Prometheus metrics, OpenTelemetry traces, structured JSON logs. Grafana dashboards included. Alerts on latency, error rate and deprecated tools.
MEF architecture in .NET. Your internal add‑ons expose tools without recompiling the core. Hot loading, hot‑swap by version, typed contract in C#.
These are four of the twelve scenarios already running in production with AretasLab clients. Measured. Audited. Under NDA — names omitted by default.
We don't reinvent the client. If Anthropic, OpenAI, Microsoft or your team builds something that speaks MCP, it already works with MCP One. These are the ones we've tested ourselves, against B1.
SAP Business One on HANA 10.0 SP02+ or SQL Server 2019+. Compatible from B1 10.0 FP 2208. Service Layer required for CRUD; SLD optional for multi‑tenant.
.NET 8 server on Linux or Windows. Deploy on Docker, Kubernetes, IIS or systemd. Self‑hosted in your infrastructure — no data egress to third parties.
MCP One is a commercial product that always deploys within your infrastructure — your data, your network, your permissions. Your team installs it; we provide the software, onboarding, and ongoing support. Priced per nominal SAP user/month, VAT not included.
Production-ready commercial product. Your team deploys it on your infrastructure; we keep the wheels turning: fast patches, managed updates, and a direct engineering channel.
For environments with complex add-ons, vertical integrations, or team needs. Assigned engineer, co-development, and extended support.
SAP already has its gateway. CData has its MCP Server. Here's the difference in a table, no fine print.
| MCP One | SAP MCP Gateway | CData MCP Server | |
|---|---|---|---|
| Self-hosted (no egress) | ✓ | ✗ | Partial |
| Write to SAP B1 | ✓ | Read-only | Limited |
| Domain-typed tools | ✓ | ✗ | ✗ |
| Custom add-ons | ✓ | ✗ | ✗ |
| n8n / LangChain compatible | ✓ | ✗ | ✓ |
| Price | €12/user/month | — | High |
| Free pilot | ✓ | ✗ | ✗ |
Honest documentation: what works, what doesn't, which versions we support and where everything is. No marketing between the lines. No hidden "coming soon".
{
"mcpServers": {
"mcpone": {
"command": "npx",
"args": [
"-y",
"@aretaslab/mcp-one",
"--service-layer",
"https://b1.yourcompany.local:50000/b1s/v1"
],
"env": {
"SBO_COMPANY": "SBOCOMP",
"SBO_AUTH": "oauth"
}
}
}
}
# Restart Claude. MCP One will appear in the 🔌 indicator
# Ask: "Which customers invoiced the least in May?"
"Zero downtime, 9 months. Patches in under 24h. I don't ask questions anymore."— R. C., CFO · Professional services
"They'd been asking for a mobile app for three years. MCP One gave it to them in two weeks."— A., Operations Manager · Food industry
"It does what it says, doesn't hallucinate joins. Serious engineering, not trade show demos."— P., Solutions Architect · SAP B1 Partner
Like at AretasLab, we don't publish client names without explicit permission. These testimonials are real — full names and companies are under NDA until the client authorizes.
I thought a SAP assistant was just hype. The first time a sales rep closed an order by voice in front of me, I stopped joking and started planning the rollout to the other 4 subsidiaries.
The warehouse team had been asking for a mobile app for three years. MCP One gave them one in two weeks — and without even an app, just talking on their phone. Zero training cost.
What I like most is how boring it is. It does what it says, doesn't hallucinate joins, and when something fails the log tells you exactly what happened. It's serious engineering, not trade show demos.
These guys being a cooperative that only works afternoons sounded like an announced bankruptcy. Nine months in, zero downtime, patches in under 24h. I don't ask questions anymore.
No evasive answers. If the answer is "it depends", we tell you what it depends on. If the answer is "not yet", we tell you when.
If your company runs on SAP B1 and you're curious to experience talking to your ERP, write to us. A 2-week pilot, at no cost for the first 5 clients of the quarter.