How to move a long Claude chat to ChatGPT without re-explaining everything

You are 80 messages into a Claude chat. The plan is half built, the decisions are made, and then you hit the usage limit. Or you want ChatGPT's take on the same problem. Either way, you open a new chat and it knows nothing.

Most people handle this in one of three ways. None of them is great.

1. Copy and paste by hand. Fine for five messages. For eighty, you lose the thread, the formatting breaks, and you spend ten minutes on it.

2. Ask the old chat for a summary. Works if the chat still has room. If you hit the limit, you can't. And a summary leaves out the small decisions you made along the way, which are exactly what you'll have to re-explain later.

3. Export the whole account. ChatGPT and Claude both offer data exports, but they give you a giant archive of every chat. You can't paste that into a new conversation.

What you want is the one chat, turned into a block of text that a different AI can read and carry on from. I'll call that a capsule: the messages in order, plus a short instruction telling the new AI to treat everything in it as already settled and to pick up from the last message.

I built a free Chrome and Edge extension, ContextPod, that does this in one click on Claude, ChatGPT and Gemini. Here is how it works.

Everything stays in your browser. There is no account and nothing is sent to a server.

I built it with Claude Code. I'd like to hear what breaks, especially on Gemini, which I've tested the least.