Kestra vs n8n API + MCP

Kestra

Kestra's open-source edition has a 216-operation OpenAPI spec, Markdown docs for agents and weekly patch releases on two long-term support lines. Its only credential is one basic-auth username and password with full access, and five critical advisories were published between March and September 2026, all fixed.

n8n API + MCP

OpenAPI 3.0 spec with 208 operations, and Markdown docs plus llms.txt. 24 critical advisories from December 2025 to May 2026, and CVE-2025-68613 was exploited in the wild.

Kestra

1. Run 2.0.5 or 1.3.42 or later. Earlier builds carry unauthenticated remote code execution advisories fixed in 1.3.38 and 2.0.3
2. Set kestra.server.basic-auth in the config file before first start. Without it the setup page is open to anyone who reaches the port
3. Put the tenant in the path. Open-source instances use main, as in /api/v1/main/executions/{namespace}/{id}
4. Send flow inputs as multipart form fields, and add wait=true to get the finished execution in the same call
5. Keep port 8081 off any shared network. The management endpoints there skip the API's basic auth

n8n API + MCP

1. Check the instance version before trusting it. Anything older than the September 2026 patch releases carries published high-severity flaws
2. Ask for only the OAuth scopes the job needs. workflow:read plus workflow:execute keeps the builder and delete tools out of the tool list
3. Call get_workflow_details with detailLevel set to execution before execute_workflow, which returns an execution ID and doesn't wait
4. Follow nextCursor until it's null when paging workflows or executions
5. On Cloud trial accounts /api/v1 won't answer. Use the MCP server or a paid plan