Company and project context can be shared across all four clients today, because each can call an external store over Model Context Protocol or a connector. Vendor-held personal memory cannot — no vendor exposes an API to read it. Conversation history is per-client by design. Knowing which of the three you mean is most of the question.
Three different things called "memory"
Almost every disagreement about cross-client memory comes from these being conflated. They have different owners and different answers.
Conversation history is the scrollback in a single thread. It belongs to that client, it is what the model sees for free within a conversation, and it ends when the thread does. It is not shareable and does not need to be — nobody wants their ChatGPT threads replayed inside Cursor.
Personal memory is the vendor feature: Claude's memory, ChatGPT's saved memories. It is stored in that vendor's account, it persists across that vendor's threads, and there is no API to read or write it from outside. This one cannot be shared, and it is worth being blunt about it: a product claiming to sync your actual Claude memories into ChatGPT is describing something neither platform permits.
Project and company context is the durable set of facts about your work — decisions, constraints, client details, project state. This one has no vendor owner, which is exactly why it can be shared. Every client listed here can call an external tool, so all of them can read from one store.
When someone asks whether there is a shared memory layer across AI clients, they almost always mean the third. The answer for that is yes.
Which clients are supported
GreatArrow.ai ships install paths for 17 clients. The four in the title, plus how each connects:
| Client | Setup | Auth |
|---|---|---|
| Claude (web, desktop, mobile) | One click from Anthropic's connector directory | OAuth |
| Claude Desktop | One-click installer | Personal token |
| Claude Code | One-liner in the terminal | Personal token |
| ChatGPT | Guided — add the connector in settings | OAuth |
| Gemini (web) | Guided — connector settings | OAuth |
| Gemini CLI | One-liner in the terminal | Personal token |
| Cursor | One-click deeplink | Personal token |
The rest of the catalogue covers GitHub Copilot and Antigravity, Codex, Kiro and Kiro Terminal, Windsurf, Zed, JetBrains, Hermes and OpenClaw. Web clients authenticate with OAuth; file-based clients (desktop apps, CLIs, editors) use a personal token stored as a one-way hash and shown once. Any other MCP-compatible client can connect to the same endpoint even without a first-class install path.
The live list, with the exact steps per client, is at /install.
What is actually shared
Once two clients are connected to the same workspace, they share:
- Facts you record. A decision stated in one client is retrievable from another.
- Content from connected sources. Email, chat, documents, issues and code from tools you have connected become searchable from every client. See Give ChatGPT and Claude Company Data With Citations.
- Sources. Retrieval returns where a fact came from, so an answer can point at the record rather than assert.
They do not share conversation scrollback, and they do not share each other's vendor memory. Those stay where they are.
The limits, stated plainly
This section matters more than the feature list, because these are the things that surprise people after setup.
Retrieval is not always-on awareness. The shared context is searched when a client decides the question calls for it. A client that does not search answers without context it could have had. Asking explicitly — "check what we know about this account first" — is more reliable than assuming.
Nothing is retroactive. Connecting a client does not import the conversations you had before. What you want carried over has to be stated once.
Write quality depends on the client. Every connected client can read. How reliably a client writes a fact without being asked varies — some are diligent about recording decisions, others need to be told. Being explicit when something matters is the practical workaround.
Managed workspaces may block connectors. Business, Enterprise and Edu tiers at OpenAI and Google can require an admin to allow connectors before you can add one. This is a policy setting on their side, not something a product can route around.
Vendor memory stays separate, permanently. Your Claude memory and your ChatGPT memories continue to exist and continue not to see each other. The shared layer sits beside them, not on top of them.
A concrete example across three clients
You are in Claude Code, working on a repository, and you settle a design question: the sync job must be idempotent, because the provider retries deliveries and a duplicate write corrupted a customer's ledger in March. You record it.
The next morning you are in Cursor in the same repository. You ask why the job is written this way. Cursor searches the workspace, finds the decision, and gives you the reason and the incident behind it — not a reconstruction from the code.
That afternoon you are writing the release note in ChatGPT and ask what changed in the sync job. Same workspace, same decision, and it can point at where the constraint was recorded.
Three clients, three vendors, one set of facts, and no re-briefing.
How it works underneath
The clients connect to a remote MCP server at https://www.greatarrow.ai/api/mcp. Model Context Protocol is an open standard for an AI client calling an external tool over a consistent interface, which is why one server serves clients from three different vendors. What Is MCP? A Guide for Teams covers it at evaluator level.
Stored content and connected-tool credentials are encrypted at rest with AES-256-GCM. Workspaces are isolated at the database layer. Client keys are one-way hashes, shown once, and revocable immediately. The security page carries the full statement.
Who this is for, and who it is not for
It is for you if you use clients from more than one vendor and keep discovering they disagree about your work.
It is not for you if you use one client and intend to keep it that way — its native memory is simpler, free, and better integrated. It is also the wrong tool if what you want is your Claude memories inside ChatGPT specifically; that is not available from anyone, and a vendor who implies otherwise is worth a second look.
Where to go next
Share Context Across Claude, ChatGPT and Cursor is the three-client setup walkthrough. Stop Re-Explaining Your Company to Every AI Tool starts with a manual template that needs no account.
Per-client setup: Claude Desktop, Claude and ChatGPT together, Cursor. The comparison page covers the alternatives; features and pricing cover capability and cost.