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Chat history compression

When a conversation grows long enough to approach the AI model's context limit, the platform automatically summarizes older messages instead of discarding them. That lets you keep extended conversations without losing important context from earlier in the chat.

Why it matters​

  • Context is preserved. Key decisions, facts, and action items from older messages are captured in a concise summary.
  • Longer conversations. You can keep chatting well beyond what the model's context window would normally allow.
  • It's automatic. Compression runs in the background when needed — there is nothing you need to configure.

What you'll see​

When compression runs during a conversation, a visual indicator appears in the chat:

  • Collapsed view: A short note that says "Chat history summarized" and how many messages were compressed.
  • Expanded view: Open it to see the full summary, token statistics for how much space was saved, and an Undo button.

Undoing compression​

To restore the original messages, click Undo on the compression indicator. The original messages return and the summary is removed. Use this when you need the exact wording from earlier in the thread.

How it works​

  1. As you chat, the platform tracks how many tokens (the units of text the model processes) your conversation uses.
  2. When the conversation nears the model's context limit, older messages are selected for compression, starting from the beginning of the chat.
  3. A summary is generated that captures the important information from those messages.
  4. The summary replaces the older messages in the context sent to the model; the originals are kept in the background.
  5. You see a compression indicator in the chat where the summarized messages were.

If something goes wrong during compression, the platform falls back to trimming older messages so the conversation can continue.

Good to know​

  • Compression is triggered automatically from conversation length and the model's context capacity. You do not enable or configure it.
  • Original messages are not deleted — they stay in the background and can be restored with Undo.
  • The summary emphasizes key decisions, important facts, action items, and context needed to continue naturally.
  • Summaries are generated with a fast, lightweight model so your chat stays responsive.
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