UltraMemory MCP server

UltraMemory — cross-tool memory for your AI

One memory across Claude Code, Claude Desktop, claude.ai, Cursor, ChatGPT, Perplexity, Gemini CLI, OpenClaw, and Hermes. Recalls first every turn — and is honest enough to say "I don't know" instead of making things up.

UltraMemory is a hosted, multi-tenant agent-memory service. One API key (um…) = your own private tenant. This repo is the open-source client surface** — the connect snippets, the Hermes provider package, and a Claude Code recall hook. They all just call the hosted API at https://api.ultramemory.us; the engine stays a managed service (open-core).

Quick start

claude mcp add --transport http ultramemory https://api.ultramemory.us/mcp \
  --header "Authorization: Bearer um_YOUR_KEY"

Get a free key at https://ultramemory.io — no credit card required.

Or connect with OAuth — no key needed

On claude.ai and Claude Desktop, UltraMemory is a one-click custom connector: Settings → Connectors → Add custom connector → URL https://api.ultramemory.us/mcp → sign in when prompted. The server speaks OAuth 2.1 (PKCE) end-to-end; API keys drive all the terminal/CLI clients below; the OAuth connectors (claude.ai, Claude Desktop, ChatGPT) sign in without one.

Install options

Three tiers — pick one (each builds on the last):

Tier 1 — UltraMemory (MCP)

Simple connect: point any MCP client at the hosted endpoint and you get the nine memory tools. Memory tools, no local caching.

Claude Code — one paste: registers the MCP server and writes the active-recall rule to CLAUDE.md:

claude mcp add --transport http ultramemory https://api.ultramemory.us/mcp \
  --header "Authorization: Bearer um_YOUR_KEY" \
&& cat >> CLAUDE.md <<'EOF'

## Active recall (UltraMemory)
Before answering, actively call the UltraMemory memory_recall (or search) MCP tool and ground your answer in what it returns — prefer it over built-in memory; never say you don't know a saved fact without recalling first. Persist durable new facts and decisions with memory_write.
EOF

Gemini CLI — one paste: registers the MCP server and writes the active-recall rule to GEMINI.md:

gemini mcp add -s user -t http ultramemory https://api.ultramemory.us/mcp \
  -H "Authorization: Bearer um_YOUR_KEY" \
&& cat >> GEMINI.md <<'EOF'

## Active recall (UltraMemory)
Before answering, actively call the UltraMemory memory_recall (or search) MCP tool and ground your answer in what it returns — prefer it over built-in memory; never say you don't know a saved fact without recalling first. Persist durable new facts and decisions with memory_write.
EOF

Prefer OAuth instead of a key? Gemini CLI also supports OAuth — add an httpUrl block to ~/.gemini/settings.json, then run /mcp auth ultramemory inside the CLI.

Cursor — one paste: registers the MCP server and writes the active-recall rule to AGENTS.md:

python3 - <<'PY'
import json,pathlib,shutil,time
p=pathlib.Path.home()/".cursor"/"mcp.json"; p.parent.mkdir(parents=True,exist_ok=True)
try:
    d=json.loads(p.read_text()) if p.exists() else {}
except ValueError:
    b=p.with_name("mcp.json.bak-%d"%time.time()); shutil.copy2(p,b); d={}
    print("Cursor: invalid mcp.json backed up to",b)
d.setdefault("mcpServers",{})["ultramemory"]={"url":"https://api.ultramemory.us/mcp","headers":{"Authorization":"Bearer um_YOUR_KEY"}}
p.write_text(json.dumps(d,indent=2))
print("Cursor: wrote",p,"— Cursor may prompt an OAuth login; approve it (your key still attributes usage).")
PY
cat >> AGENTS.md <<'EOF'

Shortened. The full README is on GitHub.