Use this skill when setup or usage of the SumUp MCP server is requested.
Canonical endpoint:
https://mcp.sumup.com/mcp
What this skill covers
- MCP server wiring in MCP-capable clients
- Auth handshake troubleshooting
- Prompt patterns for tool-driven SumUp API tasks
- Safe usage guardrails for production and sandbox contexts
Choose a Setup
If the SumUp plugin or extension is already installed, use its bundled MCP connection instead of adding a duplicate server. For a new assistant setup, prefer the packaged integration described at https://developer.sumup.com/tools/llms/plugins/.
For Codex, install the plugin from a terminal:
codex plugin marketplace add sumup/sumup-skills
codex plugin add sumup@sumup
codex plugin list
Start a new session to load its skills and tools. Complete SumUp OAuth authorization when prompted. For the Codex IDE extension, use standalone skills and a direct MCP connection.
The hosted endpoint uses OAuth access tokens issued for the MCP resource. Do not configure a SumUp API key (sup_sk_...) as its Bearer token. For API-key authentication or stdio-only clients, use the local @sumup/mcp package with Node.js 22 or later and SUMUP_API_KEY.
Direct Hosted Setup
- Add an MCP server entry named
sumup. - Set URL to
https://mcp.sumup.com/mcp. - Use streamable HTTP transport if the client requires explicit transport.
- Complete authentication flow when prompted by the client.
- Confirm tools are discoverable before first task prompt.
Codex
codex mcp add sumup --url https://mcp.sumup.com/mcp
codex mcp login sumup
codex mcp list
Complete the browser authorization flow; use /mcp in a session to inspect tools.
Claude Code
claude mcp add --transport http --scope user sumup https://mcp.sumup.com/mcp
claude mcp list
Run /mcp in Claude Code and select the SumUp server to authenticate.
Cursor
Merge this into ~/.cursor/mcp.json (all projects) or .cursor/mcp.json (one project):
{
"mcpServers": {
"sumup": {
"url": "https://mcp.sumup.com/mcp"
}
}
}
Complete authorization in Cursor's MCP settings.
For Gemini CLI, VS Code, Claude Desktop, or another client, consult https://developer.sumup.com/tools/llms/mcp-server/ and the client's current documentation. Use the client's actual configuration schema; field names differ between clients.
Local Setup
For a local stdio server with API-key authentication:
SUMUP_API_KEY='sup_sk_...' npx -y @sumup/mcp
Keep the actual key in the client's private configuration or environment. It is not a credential for the hosted OAuth endpoint.
Prompt Patterns
- "Use the SumUp MCP tools to show my merchant profile." (Read-only verification.)
- "List my SumUp merchant checkouts from the last 24 hours."
- "Create a sandbox checkout for 12.34 EUR and return the checkout id."
- "Inspect this checkout id and summarize status transitions."
- "Show what data is needed to reconcile failed payments for this reference."
Common Failure Modes
Server not reachable
- Confirm exact URL and transport.
- Check client allows outbound HTTPS.
- Retry from a clean session.
Auth loop or unauthorized
- Re-run auth handshake and ensure correct account/environment.
- For hosted connections, remove any API-key Bearer header and authenticate through OAuth. For local connections, check
SUMUP_API_KEY. - Confirm the token/session has required scopes.
Tools not appearing
- Refresh/reload MCP server in client.
- Confirm server alias matches the expected name in prompts/config.
Safety and Reliability Rules
- Never expose secrets or raw tokens in prompts or logs.
- Prefer sandbox for new workflows and regression tests.
- For payment-critical actions, verify final checkout status through deterministic reads.
- Record checkout ids/references for auditability and reconciliation.
Required Response Contract
When answering MCP setup/use requests, include:
- Exact server configuration snippet.
- Authentication steps and where failures usually happen.
- One verification command/prompt to confirm setup.
- A safe first task in sandbox before production usage.