# AI agent memory tools

> An agent without memory starts every session from zero. These tools fix that in three places. Mem0, Zep, Supermemory and Maximem Synap are memory layers you build into your own agent: they pull facts out of conversations and hand back the right ones before the model replies. Letta puts the memory inside the agent itself. DocuMemory and Skillsync are for you: they keep what you worked out with Claude Code, Cursor or ChatGPT where your next session can find it.

7 tools, in the order they appear in the Digidle Tools directory. This is not a ranking.

- Page: https://digidle.com/best/ai-agent-memory/
- All best-of lists: https://digidle.com/best/

## Tools

- [DocuMemory](https://digidle.com/tools/documemory/): Memory engine for AI-first engineers: distils Claude Code, ChatGPT and Cursor sessions into architecture decisions and prompt-injectable context blocks, recalled over MCP or a REST API; 15 free distillations, then from $10/month. Official site: https://www.documemory.dev. Alternatives: https://digidle.com/alternatives/documemory/.
- [Maximem Synap](https://digidle.com/tools/maximem-synap/): Memory and context layer for AI agents with entity resolution, temporal reasoning and scoping built in, sub-15ms recall, a hosted MCP endpoint and native adapters for 23 agent frameworks including LangChain and the Claude Agent SDK; free tier, paid from $19/month. Official site: https://maximem.ai/synap/. Alternatives: https://digidle.com/alternatives/maximem-synap/.
- [Skillsync](https://digidle.com/tools/skillsync/): Mac app and CLI that searches all your past coding-agent sessions before each prompt and hands your agent a short recollection with sources; works with Claude Code, Codex, Cursor, OpenCode, Amp and more, indexes locally, with shared team workspaces. Official site: https://skillsync.com. Alternatives: https://digidle.com/alternatives/skillsync/.
- [Mem0](https://digidle.com/tools/mem0/): Memory layer for AI agents and apps: send it conversations and it extracts, updates and retrieves the memories that matter for each user, through Python and Node SDKs, an API, MCP and a CLI. Open source (Apache-2.0) as a library or self-hosted server, or the hosted platform with a free plan. Official site: https://mem0.ai. Alternatives: https://digidle.com/alternatives/mem0/.
- [Zep](https://digidle.com/tools/zep/): Context and memory layer for AI agents: turns conversations, documents and business data into a temporal Context Graph per user, account or domain, with dated facts traced to their source and retrieval under 200 ms. Zep Cloud, your own encryption keys or your VPC; its graph engine Graphiti is open source (Apache-2.0). Free 10,000 credits a month. Official site: https://www.getzep.com. Alternatives: https://digidle.com/alternatives/zep/.
- [Letta](https://digidle.com/tools/letta/): Stateful agents with memory that persists and improves with experience, from the makers of MemGPT: Letta Code ships a terminal UI, an app server for self-hosted agents and an Agent SDK, with Letta Cloud to carry memory across machines. Open source (Apache-2.0); free with your own API keys, Pro $20/month. Official site: https://www.letta.com. Alternatives: https://digidle.com/alternatives/letta/.
- [Supermemory](https://digidle.com/tools/supermemory/): Memory and context engine for AI agents: learns from each user's chats, files and URLs, stores it in a vector-graph database and injects what matters into your agent's context, through an API, MCP and plugins for Claude Code, Cursor and more. Open source (MIT); hosted free plan with $5 of credits a month, Pro $19/month. Official site: https://supermemory.ai. Alternatives: https://digidle.com/alternatives/supermemory/.

## At a glance

| Tool | Remembers | Runs on | Open source | Price |
| --- | --- | --- | --- | --- |
| [DocuMemory](https://digidle.com/tools/documemory/) | What you worked out with AI: chats saved as decision docs and short memories any connected tool can search. | Hosted. MCP over Streamable HTTP, Claude and ChatGPT connectors, and a REST API. | No. Hosted service, source not public. | 15 free distillations, no card. Personal $10/mo, or $8/mo billed yearly. Team $15/seat/mo, 2-seat minimum. |
| [Maximem Synap](https://digidle.com/tools/maximem-synap/) | Your agent's users and organisation: facts with entity resolution, scoped per user, customer and tenant. | Hosted API, Python and TypeScript SDKs, an MCP endpoint and adapters for 23 agent frameworks. On-prem on Enterprise. | SDK and eval harness are Apache-2.0. The engine is hosted. | Trial free: 12,500 credits a month. Starter $19/mo at launch price. Pro $249/mo. Scale $999/mo. |
| [Skillsync](https://digidle.com/tools/skillsync/) | Your own coding-agent sessions, searched before every prompt and handed back as a short recollection with sources. | Mac app, indexing on your Mac. skl CLI for Linux, Windows and remote servers. | txcript, its tool for moving sessions between agents, is Apache-2.0. | Open source free. Pro $20/seat/mo with a 5-day trial, no card. Team custom. |
| [Mem0](https://digidle.com/tools/mem0/) | Your app's end users: memories extracted from conversations, updated as things change, retrieved on each turn. | Hosted platform, or the library and a self-hosted server via Docker. On-prem on Custom plans. | Yes, Apache-2.0. | Free: 50,000 adds and 10,000 retrievals a month with your own LLM key. Custom plans add graph memory, SSO and on-prem. |
| [Zep](https://digidle.com/tools/zep/) | Users, customers, accounts or domains: a temporal Context Graph built from conversations, documents and business data. | Zep Cloud, Zep Cloud with your own encryption keys, or your VPC on Enterprise. | Graphiti, its graph engine, is Apache-2.0. Zep itself is hosted. | Free: 10,000 credits a month. Flex $125/mo. Flex Plus $375/mo. Enterprise custom. |
| [Letta](https://digidle.com/tools/letta/) | The agent itself: memory, identity and skills that persist and improve with experience. | Letta Code in the terminal, desktop and web apps, a self-hosted app server, or Letta Cloud. | Yes, Apache-2.0. | Free with your own API keys, limited agents. Pro $20/mo, up to 20 stateful agents. API plans are usage-based. |
| [Supermemory](https://digidle.com/tools/supermemory/) | Users, tasks and tenants: learns from chats, files and URLs and injects what matters into context. | Hosted API, MCP and plugins for Claude Code, Cursor and more. Self-hosted on Scale and Enterprise. | Yes, MIT on GitHub. | Free with $5 of credits a month. Pro $19/mo. Max $100/mo. Scale $399/mo. |

Checked 2026-10-31 on vendor pages: [Mem0 pricing](https://mem0.ai/pricing), [Mem0 on GitHub](https://github.com/mem0ai/mem0), [Zep pricing](https://www.getzep.com/pricing), [Graphiti on GitHub](https://github.com/getzep/graphiti), [Letta pricing](https://www.letta.com/pricing), [Letta Code on GitHub](https://github.com/letta-ai/letta-code), [Supermemory pricing](https://supermemory.ai/pricing), [Supermemory on GitHub](https://github.com/supermemoryai/supermemory), [Maximem Synap pricing](https://www.maximem.ai/synap/pricing), [Synap SDK on GitHub](https://github.com/maximem-ai/maximem_synap_sdk), [DocuMemory](https://www.documemory.dev), [Skillsync pricing](https://skillsync.com/pricing), [txcript on GitHub](https://github.com/skillsynchq/txcript).

## Pick it if

- [Mem0](https://digidle.com/tools/mem0/): You want an open-source memory layer you can self-host, or start free on the hosted plan with your own LLM key.
- [Zep](https://digidle.com/tools/zep/): Your agents need facts from business data and documents, not just chat, with dates, sources and access policies.
- [Supermemory](https://digidle.com/tools/supermemory/): You want memory and document retrieval behind one API, plus plugins for the coding agents you already use.
- [Maximem Synap](https://digidle.com/tools/maximem-synap/): You're building a support or voice agent and need per-user and per-tenant memory that comes back fast.
- [Letta](https://digidle.com/tools/letta/): You want an agent that keeps its own memory and gets better over time, not a memory API to wire in.
- [DocuMemory](https://digidle.com/tools/documemory/): You work things out across Claude, ChatGPT and Cursor and want the decisions written up where all of them can read them.
- [Skillsync](https://digidle.com/tools/skillsync/): You keep re-solving problems in Claude Code or Codex that an old session already cracked.

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Source: Digidle Tools (https://digidle.com/). Full index: https://digidle.com/llms.txt