# General FAQ
SUMMARY: Common questions about Synapse — what it is, how it works, who it's for.

General FAQ
Common questions about Synapse.
What is Synapse?
Synapse is a persistent memory API for LLM agents. It gives your AI assistant
a permanent, queryable brain that survives across sessions. Instead of
forgetting everything when the chat closes, the LLM stores and retrieves
memories via a simple HTTP API.
Learn more: What is Synapse?
Who is Synapse for?
- LLM agent developers who need persistent state
- Power users running local LLMs with custom agents
- Teams building AI assistants with shared memory
- Automation engineers chaining LLM calls across sessions
Is Synapse free?
Synapse is hosted at <https://synapse.schaefer.zone> and free for personal use.
For self-hosting, see the repo.
How is Synapse different from ChatGPT Memory?
| Feature | ChatGPT Memory | Synapse |
|---------|---------------|---------|
| Storage | OpenAI servers | Your server |
| API access | No | Yes (REST + MCP) |
| Multi-tenant | No | Yes (minds) |
| Custom categories | No | Yes (8 categories) |
| Full-text search | Limited | FTS5 + semantic |
| Self-hostable | No | Yes |
What LLMs work with Synapse?
Any LLM that can make HTTP calls or use MCP:
- Claude (Anthropic) — via MCP or direct API
- GPT-4 / GPT-3.5 (OpenAI) — via function calling + API
- Gemini (Google) — via function calling + API
- Llama / Mistral (local) — via custom integration
- Any LLM via the Synapse MCP server
Do I need to host Synapse myself?
No. The hosted version at <https://synapse.schaefer.zone> is available for
public use. Self-hosting is optional (for privacy, customization, or
air-gapped environments).
How much data can I store?
There are no hard limits on the hosted version. Typical usage:
- 100-1000 memories per mind
- 1-10 KB per memory (content field)
- Total: 10 MB per mind
For larger scale, self-host.
Is my data private?
Yes. Each mind is isolated (see Multi-Tenancy).
Other users cannot see your data. The hosting provider (Schäfer Services)
has access but does not view user data.
For maximum privacy, self-host.
Can I export my data?
Yes. Use  to export all memories as JSON. See
Backup & Restore.
What happens if I lose my Mind Key?
Mind Keys are shown only once at creation. If lost:
1. Login with your email/password to get a JWT
2. Create a new mind via 
3. Save the new Mind Key
4. (Optional) Delete the old mind via 
You cannot recover memories from a mind whose key is lost.
Can multiple LLM agents share a mind?
Yes. All agents using the same Mind Key share that mind's data. For
coordinated multi-agent work, see Multi-Agent Coordination.
Does Synapse work offline?
No, Synapse requires an internet connection to the server (either hosted or
self-hosted). For offline LLMs, run Synapse locally.
How fast is memory search?
- FTS5 keyword search: < 10ms for 1000 memories
- Semantic search: 50-100ms for 1000 memories
- Full recall: < 50ms for 1000 memories
See FTS5 Search for details.
Can I use Synapse without an LLM?
Yes. Synapse is a generic memory API. You can use it from any application
that benefits from persistent, searchable key-value storage with categories
and tags.
Next Steps
- What is Synapse?
- Quick Start
- API FAQ