AgentIndex icon
AgentIndex
mnemo logo
mnemo
★ 12
vs
Perenna logo
Perenna
★ 61

mnemo vs Perenna

mnemo: Mnemo is an open, free, and unlimited persistent AI memory system featuring hybrid search and embedded synchronization. It integrates full-text search with vector search, temporal decay, and importance boosting for advanced retrieval.; Perenna: Perenna provides a lightweight, Git-backed permanent memory solution for various AI agents, enabling them to share durable memories without vendor lock-in. It stores human-readable Markdown in a Git repository and uses a local Vexor index for retrieval, ensuring memory persistence across different agents and machines.

01

TL;DR

mnemo logo
mnemoMemory & Context · ★ 12

Providing persistent long-term and short-term memory for AI agents to enhance their context and decision-making.

Read mnemo full review →
Perenna logo
PerennaMemory & Context · ★ 61

Sharing durable memories across different AI agents like Claude Code, Codex, ChatGPT, and Cursor.

Read Perenna full review →
02

Side-by-Side Comparison

Field
mnemo logomnemo
Perenna logoPerenna
Category
Memory & Context
Memory & Context
Stars
★ 12
★ 61
License
Apache-2.0
MIT
Install Command
/plugin marketplace add n24q02m/claude-plugins && /plugin install mnemo-mcp@n24q02m-plugins
uv tool install perenna
Updated
1d ago
1mo ago
Open Source
Yes
Yes
Website
↗ Visit
↗ Visit
GitHub
↗ GitHub
↗ GitHub
Tags
AI Memory, Hybrid Search, Vector Database
AI Memory, Agent Tooling, Git-backed Storage
03

Features

mnemo logomnemo
01Hybrid retrieval combining full-text search (FTS5) and vector search, fused via Reciprocal Rank Fusion, then re-ranked with temporal decay and importance boost.
02Automatic entity extraction and relation tracking to build a temporal knowledge graph, boosting top search results by graph proximity.
03Multi-machine sync via Google Drive with JSONL-based merge sync, and end-to-end encrypted passport sync using AES-256-GCM and Argon2id for secure cross-device bootstrap.
04LLM-driven compression of older memories and LLM summarization of related memories for STM-to-LTM consolidation, achieving significant token reduction.
05Zero-config local setup using Fastretrieval's built-in Qwen3 ONNX embedding and reranking models, requiring no external API keys for basic operation.
Perenna logoPerenna
01Git-backed permanent memory storage in human-readable Markdown.
02Local Vexor retrieval index that can always be rebuilt from Git.
03Support for various AI agents and MCP clients to share memory.
04Self-hosted with no account or proprietary cloud lock-in.
05Cross-process locking for multiple local agent processes.
04

Use Cases

mnemo logomnemo
↳Providing persistent long-term and short-term memory for AI agents to enhance their context and decision-making.
↳Building and querying a temporal knowledge graph to understand historical states and relationships of entities within an AI system's memory.
↳Synchronizing AI memory across multiple machines or devices securely, enabling a consistent knowledge base for agents.
↳Improving the efficiency of LLM interactions by compressing older memories and consolidating related information.
↳Integrating with various AI clients (e.g., Claude Code, Gemini CLI, Cursor) as an MCP server for advanced memory management.
Perenna logoPerenna
↳Sharing durable memories across different AI agents like Claude Code, Codex, ChatGPT, and Cursor.
↳Self-hosting a private and controllable AI agent memory service.
↳Inspecting, editing, versioning, and backing up AI agent memories.
↳Ensuring AI agent memory persistence when switching between agents or machines.
FAQ

FAQ

What is the difference between mnemo and Perenna?
Both mnemo and Perenna are in the Memory & Context category. mnemo has 12 stars, while Perenna has 61 stars.
Which is better, mnemo or Perenna?
The best choice depends on your use case. Choose mnemo if Providing persistent long-term and short-term memory for AI agents to enhance their context and decision-making., and Perenna if Sharing durable memories across different AI agents like Claude Code, Codex, ChatGPT, and Cursor..
Is mnemo free or open source?
Yes, mnemo is open source on GitHub (Apache-2.0).
Is Perenna free or open source?
Yes, Perenna is open source on GitHub (MIT).
Cloud Infrastructure
Ad

Deploy on DigitalOcean

Host your MCP servers, Docker containers, and AI agents with $200 free credit over 60 days.

Claim $200 Free Credit
→

Related

Alternatives to mnemo →Alternatives to Perenna →mnemo details →Perenna details →