Open sourcePython · ≈156k stars · MIT
Langflow
Visual builder for deploying AI agents and workflows as APIs and MCP servers.
Langflow is an open-source platform for building and deploying AI agents and workflows. It combines a visual builder with Python-level access to customize any component, an interactive playground for step-by-step testing, multi-agent orchestration with conversation management and retrieval, and deployment as an API, exported JSON or an MCP server that exposes flows as tools. It integrates with LangSmith, Langfuse and other observability tools, and ships a desktop app for Windows and macOS.
Pros & cons
Each point cites its sources and says what kind of evidence backs it. A second reviewer tried to refute every claim before it was kept.
Pros
- DocsVisual, Python-based builder for RAG and multi-agent flows that is model-, API- and database-agnostic.[1]
- MetadataMIT-licensed and actively released (v1.13.0 on Oct 22, 2026; about 156k stars).[1]
- DocsBacked by IBM (via its DataStax acquisition), which pledged continued open-source support and watsonx integration.[1]
Cons
- Independent testCVE-2025-3248, an unauthenticated RCE in the code-validation endpoint (CVSS 9.8), was exploited in the wild and added to CISA KEV in May 2025.[1]
- DocsOnly in 1.13 did official packages, source archives and Docker images start setting LANGFLOW_AUTO_LOGIN=false by default.[1]
- DocsUpgrades need care: the release notes advise trying new versions in a fresh venv or VM first, and 1.13 moved local Knowledge and Memory from Chroma to SQLite and removed the ALTK component.[1]
- User reportsUsers call the visual-workflow market saturated and expect consolidation, which raises long-term uncertainty for builders like this.[1][2]
- Best for
- Teams prototyping RAG or agent flows visually who want an MIT tool they can self-host.
- Watch out for
- Never expose an instance to the internet without auth, and upgrade from older versions with a migration test plan.
Assessed Oct 29, 2026 · adversarially reviewedSuggest a correction
People
Engineer
Lead maintainer
Harness engineering
Founder & CEO
Harness engineering
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Connections
Relations from the Harness Hub knowledge graph, as charted in the State of Harness reports.
Maintained by · 1
- LangflowOrganisation
Built on · 1
- Model Context ProtocolProject
Sources
Verified Oct 29, 2026