ChatGPT/Codex

Where	How
Codex (CLI and app)	The HyperMemory plugin
ChatGPT	A developer mode connector plus custom instructions

Codex

Install with one instruction

Paste this into Codex:

Install the HyperMemory plugin from https://github.com/hypermemory-ai/hm-plugins-openai
(first make sure Python 3 and Git are installed on this computer and install them if
they are missing), then start the HyperMemory OAuth sign-in so the authentication page
opens in my browser and wait for me to approve it, and finally download and install the
latest HyperMemory skill.

Codex will:

Check that Python 3 and Git are installed — the plugin’s hooks use them.
Add the hypermemory-ai marketplace and install the hypermemory plugin.
Open HyperMemory’s sign-in page in your browser. Sign in and approve the connection.
Fetch the latest HyperMemory skill with hm_skill.

Then run /hooks in Codex and trust the HyperMemory hooks — Codex skips plugin hooks until you do. See Codex plugin for what the plugin installs and how to update or remove it.

Install it yourself

codex plugin marketplace add hypermemory-ai/hm-plugins-openai
codex plugin add hypermemory@hypermemory-ai

ChatGPT

ChatGPT connects to HyperMemory as a custom MCP connector in developer mode, on the ChatGPT plans that support custom connectors.

Turn on developer mode

In ChatGPT, open Settings → Apps & Connectors → Advanced settings and turn on Developer mode.

Add the connector

Create a connector named HyperMemory with the MCP server URL and OAuth authentication:

https://api.hypermemory.io/mcp

ChatGPT opens HyperMemory's sign-in page. Sign in and approve the connection.

Add the instructions

Copy the custom instructions from the Integration page in the HyperMemory dashboard into Settings → Personalization → Custom instructions. They tell ChatGPT to recall before replying and to save what it learns.

Use it in a chat

In each new chat, select HyperMemory from the tools menu.

ChatGPT asks you to confirm write actions such as hm_store; you can allow them for the rest of the conversation. ChatGPT doesn’t expose token counts, so its hm_tokens reports are estimates.

Verify

Ask:

What do you know about me?

The agent should call hm_recall before answering.