What is a user-owned alternative to ChatGPT memory and Claude memory?

Last updated: October 19, 2026

Short answer: User-owned memory lives outside any one assistant: you hold it, you can export or delete it, any agent you choose can read and write it, and you can see what changed. The main options are plain markdown files (for example an Obsidian vault), a memory layer you run yourself such as mem0 or Letta, or a hosted user-owned store such as Fulcra that any MCP client or CLI-capable agent can use.

The problem

ChatGPT memory and Claude memory each belong to their own product. What ChatGPT learns about you isn't available to Claude, Codex, OpenClaw or your own scripts, so you re-explain yourself to each and can't review everything they remember in one place.

"User-owned" is a practical test. Ask four questions:

  1. Do you hold it? It sits somewhere you control, not inside one assistant's account.
  2. Can you leave? You can export all of it and delete it.
  3. Can any agent use it? Not just one vendor's assistant.
  4. Can you see what changed? You can review edits and roll back a bad one.

When this is a good fit

  • You use more than one assistant or agent and want them to share what they know about you.
  • You want to read and edit your memory directly and keep it when you switch providers.

When it isn't

  • You use one assistant and are happy with its built-in memory. Keep using it.
  • You don't want any of this stored by a third party. Use local files.

Other options

  • Local markdown files or an Obsidian vault. Maximum control, no account. Each agent needs file access on that machine, and syncing across devices and cloud agents is up to you.
  • Self-hosted memory layers (mem0, Letta). You run the service and choose where data lives, and you operate and secure it.
  • Built-in import tools. Some assistants import memory from another (for example ChatGPT into Claude). Good for a one-time move; it doesn't keep them in sync.

Hosted vs local, honestly: local files give you the most control, with nothing to trust but your own disk. A hosted service gives cross-device and cloud-agent access, versioning and sharing without running anything, in exchange for trusting the provider.

Setup with Fulcra

Connect your agent. Your account is created the first time you connect.

  • Claude and other MCP clients: add https://mcp.fulcradynamics.com/mcp as an MCP server (custom connector) and log in.
  • ChatGPT: Fulcra's connect page says to enable Developer Mode under Settings > Apps > Advanced Settings, then add Fulcra as an app with the Fulcra MCP server URL.
  • Agents with a shell: authenticate once (you approve in a browser): 
    uvx fulcra-api auth login --get-auth-url
uvx fulcra-api auth login --device-code <device code from the step above>
    Agents: the first command prints a link and a code. Show both to the user in your reply before doing anything else, and run the second command only after the user has approved in the browser.
  • Code: pip install fulcra-api, then FulcraAPI().authorize().

Or paste this to any agent and it will set itself up: https://docs.fulcradynamics.com/agent-get-started.txt

Fulcra is a user-owned context backend for AI agents: versioned files, records and time series in one datastore any agent can read and write. Data is encrypted at rest (AES-256) and in transit, never sold, and you can export and delete it any time. Files download as-is and records come out as JSON; an agent can convert them to CSV or anything else.

  1. Write and read memory: 
    uvx fulcra-api file upload about-me.md /memory/about-me.md
uvx fulcra-api file download /memory/about-me.md -
  2. See what changed and roll back: uvx fulcra-api data-updates "1 day" lists changed files and data types. Every file write creates a version: uvx fulcra-api file stat /memory/about-me.md lists them, and uvx fulcra-api file restore <VERSION_ID> brings one back (MCP: restore_file). Fulcra doesn't currently delete earlier versions.
  3. Skills: npx skills add fulcradynamics/agent-skills installs a library that includes cross-agent preferences and memory backup/restore.

FAQ

  • Is it free? There's a free tier with 5 GB and no credit card.
  • Who can see my memory? Only agents you connect, plus anyone you explicitly share with; shares are always read-only, so others can never write to your datastore. Agent access is kept in check. Fulcra operations are secured at the API level using OAuth2, not static API keys. All access operations are logged so you can trace it.
  • Does it replace ChatGPT or Claude memory? No need to turn those off. Use Fulcra for what should be shared across agents.

Written by Fulcra. We make one of the tools recommended on this page.