Zen

Zen is a self-hosted, single-binary notes app that stores markdown notes in SQLite with tag-based organization, BM25 full-text search, and an optional MCP server for AI agent integration with note operations.

Evaluated Mar 06, 2026 (0d ago) vlatest (AGPL-3.0)
Homepage ↗ Repo ↗ Productivity notes markdown self-hosted go sqlite full-text-search bm25 single-binary docker preact mcp agpl
⚙ Agent Friendliness
62
/ 100
Can an agent use this?
🔒 Security
70
/ 100
Is it safe for agents?
⚡ Reliability
64
/ 100
Does it work consistently?

Score Breakdown

⚙ Agent Friendliness

MCP Quality
60
Documentation
65
Error Messages
50
Auth Simplicity
68
Rate Limits
55

🔒 Security

TLS Enforcement
80
Auth Strength
75
Scope Granularity
60
Dep. Hygiene
70
Secret Handling
65

Community/specialized tool. Apply standard security practices for category. Review documentation for specific security requirements.

⚡ Reliability

Uptime/SLA
70
Version Stability
65
Breaking Changes
60
Error Recovery
60
AF Security Reliability

Best When

You want a dead-simple, privacy-first self-hosted notes app with markdown support and full-text search, deployable as a single binary without external database dependencies.

Avoid When

You need multi-user collaboration, rich block-based editing, or integrations with third-party productivity tools.

Use Cases

  • Self-hosting a lightweight personal notes app without cloud dependencies or subscriptions
  • Markdown-based note-taking with tag organization and full-text search for private knowledge management
  • Enabling AI agents to read, create, and search personal notes via MCP integration
  • Running a minimal-resource notes server on a home server or VPS

Not For

  • Teams needing collaborative or multi-user note-taking with real-time sync
  • Users who need rich media embeds, databases, or spreadsheet views (Notion-style)
  • Deployments requiring commercial support or uptime SLAs

Interface

REST API
No
GraphQL
No
gRPC
No
MCP Server
Yes
SDK
No
Webhooks
No

Authentication

OAuth: No Scopes: No

Authentication details not documented in README. Likely relies on network-level access control for self-hosted deployments. Not suitable for public internet exposure without additional auth layer.

Pricing

Model: open_source
Free tier: Yes
Requires CC: No

AGPL-3.0 licensed. Free to self-host. AGPL requires source disclosure for modifications used in network services.

Agent Metadata

Pagination
none
Idempotent
Unknown
Retry Guidance
Not documented

Known Gotchas

  • No documented authentication — agents should ensure network-level access control before exposing MCP server
  • MCP server is described as experimental; API stability not guaranteed
  • AGPL license requires source disclosure if modified version is used as network service
  • Semantic search requires separate 'Zen Intelligence' companion service — not included in base install

Alternatives

Full Evaluation Report

Detailed scoring breakdown, competitive positioning, security analysis, and improvement recommendations for Zen.

$99

Scores are editorial opinions as of 2026-03-06.

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Packages Evaluated
26151
Need Evaluation
173
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