Tutorial · Task guide
Long-Book Context: Why the AI Remembers — or Forgets — Earlier Chapters
Before you start
- A book imported and continued at least a few times, as covered in ‘Import and Continue a Novel Without Overwriting the Original’.
- A connected text model through the official channel or BYOK, and access to Me → Request records for cost checks.
- For books with many paths, read ‘Manage Story Branches: Create, Switch, Compare, and Choose’ first; this guide focuses on memory and cost along one line.
Where to find it
Reader > top bar > Book info > AI feature settings > Smart context > Context slimmingReader > top bar > Book info > Book AI material > Book material injected into the AIReader > top bar > Book info > Book AI material > Book loreReader > top bar > Book info > Edit worldMe > Request records
Step-by-step
Know what the AI actually reads
The model does not reread the whole book. Each continuation sends one context window: text near your current position, this book's AI material (world setting, Book lore, imported cards), and your instruction. Whatever does not fit is invisible for that request — most ‘forgetting’ is simply a scene that did not make the window.
✓ You can state it plainly: remembered means it was in the window, forgotten means it was not.
Verify what was sent
Open Book info → Book AI material → Book material injected into the AI to see each block and a token estimate. After generating, open Me → Request records to read the final request, its token counts, and timing. When the AI seems to forget, check these two places before rewriting your instruction.
✓ You can find a continuation in request records and name the blocks it carried.
Put durable facts where they persist
Rules that should always hold — relationships, world laws — belong in Book info → Edit world, or as entries in Book lore. Lore entries trigger by keyword by default: they join the request only when your input mentions them, so they do not waste window space. One-off requirements can just go in the instruction.
✓ When your input hits a lore keyword, the continuation follows that entry and reports how many entries were attached.
Turn on Context slimming for a long book
Open Book info → AI feature settings → Smart context → Context slimming. When on, AI-written passages far behind your position are compressed into one-line plot digests for the context: more of the original novel stays in the window, which eases style drift, and distant plot survives as digests instead of being pushed out entirely. On the official channel the first switch-on shows a one-time cost note; nothing runs until you confirm Turn on.
✓ The toggle is on and you have read the cost and gradual-effect notes in the dialog.
Confirm the effect and the spending
Digests fill in gradually — a few passages per continuation, so a book with many existing AI passages takes dozens of rounds to catch up, and that is by design. In Me → Request records you will see small digest calls tagged reader:segment-summary, and inside later continuation requests the distant AI passages appear as single digest lines.
✓ Request records show both the digest calls and a continuation whose distant passages are one-line digests.
How to know it worked
- You can point at the injection preview or a request record and name what a continuation carried.
- Durable facts live in Edit world or Book lore and attach automatically on keyword hits.
- With Context slimming on, digest calls appear in request records while the book text and reading view stay untouched.
- After turning the toggle off, the next request returns to full-text form and existing digests are kept.
Cost, data, and irreversible-risk notes
- Reading, changing settings, the injection preview, and lore management are free. Every continuation is billed by tokens on the selected model — official channel at 1 credit = US$0.0001, BYOK by your provider. A bigger window means more tokens and higher cost.
- Context slimming adds small digest generations: each passage is digested once and then reused. Every call is listed in Me → Request records tagged reader:segment-summary, so whether money was spent is always checkable.
- Generated digests are stored with this book. Turning the feature off does not delete them, turning it back on does not pay again, and digests never touch the book text — they exist only inside AI requests.
- To stop new digest spending, turn the toggle off; continuations immediately return to full-text form. Digest calls already made are real completed requests and are not refunded.
Troubleshooting
The AI forgot events from many chapters ago
Likely cause: That scene is too far behind your position and fell outside the context window; the model cannot see outside the window.
What to do: Move durable facts into Edit world or Book lore, state the critical event in the instruction for this one generation, and turn on Context slimming so distant plot stays present as digests.
Continuations drift away from the original style
Likely cause: Near the tail of a long book the window fills up with earlier AI passages, crowding out the original author's prose.
What to do: Keep Annotate AI paragraphs on so the model can tell source from continuation, and turn on Context slimming so distant AI passages shrink to one line and original text returns to the window. It eases drift; it does not erase it, since recent AI passages remain in full.
Context slimming is on but nothing seems different
Likely cause: Digests fill in gradually — only a few per continuation — and books with few distant AI passages do not trigger slimming at all.
What to do: Keep reading and continuing normally, and use the reader:segment-summary entries in request records as proof it is working. There is no need to toggle it off and on.
No digest lines in a request
Likely cause: Annotate AI paragraphs was turned off (slimming depends on it), or this was a mid-book insertion — digests only apply to tail continuations and plot candidates.
What to do: Re-enable Annotate AI paragraphs under Smart context. Mid-book insertions and rewrites carrying full text is normal behavior.
Token cost is higher than expected
Likely cause: The context budget defaults to Auto and scales with the selected model's capacity, and long books naturally carry a lot of text plus material.
What to do: Set a hard cap in the advanced budget under AI feature settings (only a value you enter yourself takes effect), pick a cheaper or smaller-window model, or use Context slimming — distant AI passages then cost one line each. Verify with the token counts in request records.
Frequently asked questions
Does the AI read the whole book every time?
No. Each generation carries only the context window: recent text, this book's material, and your instruction. The model has no memory of anything outside it.
Will Context slimming change my book text?
No. Digests exist only inside the requests sent to the model. The book text and the reading view do not change by a single character, and turning the toggle off restores full-text requests immediately.
How accurate are the digests?
A digest keeps concrete facts and foreshadowing but is not the original wording, so distant details can be off. That is still far more reliable than the alternative — once a passage is pushed out of the window entirely, the model tends to invent old plot confidently. Recent story always stays as full text.
Why is it off by default?
Because it spends money automatically, in small amounts. The app's rule is that paid automatic behavior must be explained and confirmed first, so it is opt-in with a one-time cost note.
My roleplay character forgot things — same fix?
No. Character-chat memory runs on cards, worldbooks, and chat summaries; use “Fix ‘The Character Forgot’: Memory, Lorebook, Context, and Prompt Checks” for that. This guide covers Reader continuations only.
Sources and verification
- Reader guide · Foreverse · Verified
- Models and Usage guide · Foreverse · Verified
Coverage and verification
| Platform | Android Reader |
|---|---|
| App version | v76+ |
| Path verified |