Use Synapse with ChatGPT

Add persistent memory to any Custom GPT using Synapse Actions. Your GPT will remember everything across conversations — no more starting from scratch every session.

Step 1: Get a free API key

Sign up at synapse.by-kit.com/signup. Your key is shown once at creation — save it immediately.

Step 2: Create a Custom GPT

Go to chat.openai.com → Explore GPTs → Create. Give your GPT a name and description.

Step 3: Add a Synapse Action

  1. In the GPT editor, go to Configure → Add actions
  2. Click Import from URL and paste this schema URL — it loads everything automatically:
    https://synapse.by-kit.com/openapi.json

    Or download directly: openapi.json ↓

  3. In Authentication: select API Key, type Bearer, paste your Synapse API key
  4. Add these instructions to your GPT's system prompt:
    You have Synapse memory tools (synapse_remember, synapse_recall, synapse_recent). At the start of every conversation, call synapse_recall with query='recent context'. Save important facts immediately with synapse_remember.

Save and publish your GPT. It will now load your Synapse memory at the start of every conversation and save important facts automatically.

Works with Claude Code too

If you use Claude Code (the CLI), you can also install the Synapse MCP package via npm:

npm install -g synapse-memory-mcp

See the Claude Desktop guide for full setup instructions including the config file and system prompt.

Next steps