qrblox-mcp · v0.1

Qrblox MCP

qrblox-mcp is the JSON-RPC MCP server that gives AI agents safe, merchant-scoped tools. Sign in to Qrblox Create, mint a sk-qrblox- key, paste it into Claude Desktop or Cursor, and the agent can draft QR codes, audio codes, menus, and scan challenges — and read scan analytics — for one merchant workspace, nothing more.

Get an API key → See the tools

What it is

The Qrblox MCP server (qrblox-mcp) connects AI agents to merchant-owned Qrblox data over the Model Context Protocol. A merchant mints an API key in Qrblox Create, pastes it into Claude Desktop, Cursor, or a custom agent, and the assistant can draft QR codes, audio codes, menus, and loyalty challenges — and summarize scan activity — all scoped to that one merchant workspace.

Draft-first by design. Creation tools produce drafts. High-risk publishing, billing, and destructive changes stay in the merchant's hands inside Qrblox Create — the agent proposes, the merchant approves.

Get an API key

MCP keys are merchant-scoped and created in Qrblox Create:

1. Sign in
Go to create.qrblox.com and sign in with Google.
2. Open API keys
Navigate to Settings → API keys.
3. Create a key
Click New API key. Qrblox mints a key shaped like sk-qrblox-<64 hex chars> for your merchant workspace.
4. Copy it once
The plaintext key is shown a single time. Copy it into your agent now — Firestore stores only a SHA-256 hash and a short prefix, and can never show it again.
5. Revoke anytime
Revoking a key rejects it on the very next request.

Keys carry merchant-scoped permissions:

merchant:read
Read the merchant workspace and its QR codes, menus, and scan summaries.
qr:write
Create draft QR codes.
menu:write
Create menus and add menu items.
audio:write
Create draft audio codes.
challenge:write
Create draft scan challenges and loyalty campaigns.

Authentication

Send the key as a Bearer token. Keys begin with sk-qrblox- and are validated against Firestore on every request; the matching record carries the merchant id and scopes that the tool layer enforces.

authorization headerhttp
Authorization: Bearer sk-qrblox-4c2fa8e1b7d9…

The server also accepts a Firebase ID token or a session cookie for in-app callers on Qrblox Create. External agents use the sk-qrblox- API key — that is what this page covers.

Endpoint and transport

One endpoint: POST https://api.qrblox.com/mcp. Standard MCP JSON-RPC 2.0 envelopes in the body, a single JSON-RPC response in the reply. A GET on the same URL returns server metadata (name, endpoint, docs link). Each POST is stateless — no session handshake between requests.

calling a toolhttp
POST /mcp HTTP/1.1
Host: api.qrblox.com
Authorization: Bearer sk-qrblox-…
Content-Type: application/json

{"jsonrpc":"2.0","id":1,"method":"tools/call",
 "params":{"name":"qrblox.qr.list",
  "arguments":{"limit":10}}}

Supported JSON-RPC methods:

  • initialize — handshake. Returns protocolVersion 2025-03-26 and server info (qrblox-mcp). No auth required.
  • notifications/initialized — accepted as a notification; replies 204 No Content.
  • ping — protocol-level liveness probe; returns an empty result. No auth (distinct from the qrblox.ping tool).
  • tools/list — discover the tool registry. Requires auth.
  • tools/call — invoke a tool by name with { name, arguments }. Requires auth.

Tools

qrblox.ping
Confirm the server is reachable for the authenticated merchant. No arguments. Returns ok, merchantId, and authMethod.
qrblox.merchant.get_profile
Get the merchant workspace attached to this user or API key. No arguments.
qrblox.qr.list
List recent QR codes for the merchant. Optional limit (1–100).
qrblox.qr.create
Create a draft QR code for a URL, menu, offer, or campaign landing page. Required: title, destinationUrl. Optional: campaign, tags (string array).
qrblox.audio.create
Create a draft audio code payload that can later be published as a near-ultrasonic sharing experience. Required: title, payloadText. Optional: campaign.
qrblox.menu.create
Create a merchant menu that can be connected to QR codes, audio codes, and scan experiences. Required: name. Optional: description, locationId.
qrblox.menu.list
List recent menus for the merchant. Optional limit (1–100).
qrblox.menu.add_item
Add an item to a section in an existing menu. Required: menuId, sectionName, name. Optional: description, price (number).
qrblox.challenge.create
Create a draft scan challenge, streak, game, or loyalty campaign. Required: name, challengeType (streak, scan_count, visit_window, or game). Optional: description, rewardText, startsAt, endsAt (ISO dates).
qrblox.analytics.scan_summary
Summarize recent scan activity for the merchant workspace. Optional days (1–365).

Every tool re-derives the merchant from the verified caller, so an agent can only ever read and write within its own merchant workspace.

Example call

tools/call → qrblox.qr.createjson
{
  "jsonrpc": "2.0",
  "id": "create-menu-qr",
  "method": "tools/call",
  "params": {
    "name": "qrblox.qr.create",
    "arguments": {
      "title": "Table 12 lunch menu",
      "destinationUrl": "https://qrblox.com/m/table-12",
      "campaign": "Lunch menu rollout",
      "tags": ["menu", "table-12"]
    }
  }
}

Errors

Tool results come back as JSON-RPC result objects; failures come back as JSON-RPC error objects. Auth failures carry a data.code of NO_AUTH, INVALID_API_KEY, INVALID_TOKEN, or REVOKED.

400 · -32600
Body is not a valid JSON-RPC 2.0 request (bad JSON or missing method).
401 · -32001
Missing or invalid key / token.
403 · -32001
Key was revoked. Mint a new one.
200 · -32601
Unsupported JSON-RPC method.
200 · -32602
Missing or unknown tool name.
200 · -32000
Tool handler threw — read error.message.

Security model

Merchant-scoped
Every API key is tied to one merchant workspace and one owner or member uid. Tools cannot reach another merchant's data.
Hashed keys
Plaintext keys are shown once. Firestore stores only a SHA-256 hash and a short prefix.
Audited tools
Each tool call writes an audit event with the caller, tool name, and status — without storing full arguments or result payloads.
Draft-first
Creation tools produce drafts; publishing, billing, and destructive changes stay with the merchant in Qrblox Create.

Connect snippets

Claude Desktop

~/Library/Application Support/Claude/claude_desktop_config.jsonjson
{
  "mcpServers": {
    "qrblox": {
      "url": "https://api.qrblox.com/mcp",
      "headers": { "Authorization": "Bearer sk-qrblox-…" }
    }
  }
}

Cursor

In Cursor settings, add a new MCP server with the same URL and Authorization header.

curl (smoke test)

tools/call → qrblox.pingbash
# Expect: { ok: true, merchantId: "…", authMethod: "api-key" }
curl -s https://api.qrblox.com/mcp \
  -H "Authorization: Bearer sk-qrblox-…" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"qrblox.ping","arguments":{}}}'

Looking for the rest of the stack? Web Portal · Canva app · All docs