SAIHM — memory for AI agents

Portable memory for AI agents. Your assistant remembers what matters — across sessions, across models, across vendors. Share a memory with someone else's agent, take it back, or erase it for good.

AI assistants forget everything when the session ends. SAIHM gives yours a memory that doesn't — one that follows you to a different assistant, a different model, or a different company's product.

Everything is encrypted on your own machine before it goes anywhere, so nobody else can read your memories. Not the storage, not SAIHM.

Start free — one command

npx -y @saihm/mcp-server-pro free-join

That's it. No card, no account to fill in, nothing to invent. It sets up your identity on this machine and prints a one-time sign-in to confirm you're a real person. Open the link, enter the short code, approve.

Then point your AI tool at it. This works in Claude Desktop, Claude Code, Cursor, Cline, and anything else that speaks MCP — add the "saihm" entry inside your existing mcpServers section:

{
  "mcpServers": {
    "saihm": {
      "command": "npx",
      "args": ["-y", "@saihm/mcp-server-pro"],
      "env": {
        "SAIHM_ENDPOINT_URL": "https://saihm.net/mcp"
      },
      "timeout": 60
    }
  }
}

Restart the connection and say "Recall my SAIHM memories." You're running.

Two details in that config are load-bearing:

• Keep timeout: 60. Some tools allow as little as 1.5 seconds for a server to start, which isn't long enough for npx to fetch and launch a package. A server that misses the deadline is skipped silently — the tools simply never appear, and nothing in the chat says why.
• No trailing commas. These files are strict JSON. A stray comma doesn't just break this entry; it invalidates the whole file and every other tool you had configured disappears with it.

Prefer not to touch a terminal? Add the config above first, then say "Join SAIHM" to your assistant. It does the same setup for you.

Things to say

You don't call tools by name — you talk to your assistant. Some starters:

Liberally use SAIHM protocol to maximize token economy.

Recall my SAIHM memories before you start.

Remember that I prefer short answers and no preamble.

Set an invariant to doubly confirm before any SAIHM forget action.

Share that note with my colleague's agent until 5:00 pm today.

How much of my SAIHM allowance is left?

Forget everything I told you about the Henderson account.

Every tool is labelled for your AI tool to read, including which are read-only and which one destroys data — so hosts that ask "are you sure?" before destructive actions know when to ask. Two further tools, saihm_governance_propose and saihm_governance_vote, are registered for a roadmap feature and are not yet active.

"Forget" really means forget. The key to that specific memory is destroyed, so the stored copy becomes permanently unreadable — by you, by SAIHM, by anyone holding a backup of it. This is how SAIHM answers a GDPR Article 17 erasure request, and it is why there is no undo.

Your memories follow your key

Your memory belongs to your key, not to a computer — that's what makes it portable. The key is created on your machine during setup and never sent anywhere, which is exactly why nobody else can read your memories. Keep a copy of the key file somewhere safe. SAIHM cannot make you another one.

Setup prints the file's location when it runs — that's the line to keep. The same key carries through if you upgrade to a paid plan: same identity, same memories, nothing migrated.

Using a second computer? Two ways:

• Same memory, both machines — put your key file on the second machine, set up the config there, and say "Recall my SAIHM memories."
• Work and personal kept apart — start fresh on the second machine and share across instead: "Share these notes with my work agent until 5:00 pm." A share can be revoked or given an expiry, so the two stay separate.

See it run

• Live demos across every major model — offline, about a minute each, no account: https://citw2.github.io/saihm-demos/. Store a memory in Claude, GPT, DeepSeek, Qwen, Kimi, or GLM, then prove you can erase it.
• Token benchmark — recalling a bounded set of memories instead of re-sending the whole conversation cut input tokens by 62.8%–85.9% across a realistic multi-session task. Open, offline, reproducible: https://github.com/citw2/saihm-token-benchmark.

What it costs

Start free. The free tier is a fixed, one-time allowance of writes, reads, and shares for trying SAIHM on real infrastructure — it doesn't reset or refill. No card, and nothing to cancel. Your assistant shows what's left and warns you as it runs low, so nothing fails by surprise.

Paid plans are monthly. Upgrading keeps the same key and every memory you already have:

SAIHM_MASTER_SECRET_FILE=$HOME/.saihm/free-identity.key \
SAIHM_TIER=FREE \
  npx -y @saihm/mcp-server-pro upgrade PRO

That prints a checkout link tied to your identity. Pay, then add two lines to your config's env block and restart:

"SAIHM_TIER": "PRO",
"SAIHM_PAYMENT_METHOD": "stripe"

Both are needed — a paid plan without SAIHM_PAYMENT_METHOD refuses to start, because that setting names which payment rail to check. stripe is one option; stablecoin is another, and your assistant can tell you what your operator accepts.

If something isn't working

How it works

In plain terms. Everything is encrypted on your machine before it is sent, and decrypted on your machine after it comes back. What's stored is unreadable ciphertext and no key that opens it. To erase something, its key is destroyed — which is why erasure is immediate and final rather than a promise that a copy was deleted somewhere.

For the technically inclined.

• Encrypt before send — remember encrypts client-side; recall decrypts client-side. Your plaintext, master secret, and key-encryption key never leave this process.
• Post-quantum — ML-DSA-65 for identity and signing, ML-KEM-768 for authenticated sharing, via @saihm/client-pro.
• Crypto-shred erasure — forget destroys the endpoint-side wrapped data-encryption key, rendering the cell undecryptable (GDPR Art. 17).
• Erasure that travels — forget also appends one line to a per-identity feed, so anything that derived from a cell — an index, a mirror, an extracted fact — can be told to drop it too. An erasure that stops at this substrate is not an erasure. On by default; SAIHM_ERASURE_FEED=0 turns it off.
• Standard transport — POST {method, params} with Authorization: Bearer <JWT>; the endpoint binds your tenant from the JWT. HTTPS only, with loopback http permitted for local development.
• Self-onboarding — with no SAIHM_AUTH_HEADER set, the client proves control of your identity and mints its own short-lived token, refreshing transparently. You paste one config once and never re-paste a token. Cancelling a subscription stops the next refresh, so access ends naturally.

Security model

Where encrypted cells are stored