Two reads still grew without bound after the snapshot fix.
`Action.variants` holds every discarded retry attempt, but a list response
only needs how many there are — so each retry permanently added ~5 KB to
every later load of that adventure. Defer the column and keep the count
beside it (migration 37, backfilled server-side), with set_variants() as the
one write path that keeps the two in step.
`story_actions()` walked adventure.actions, then every caller threw almost
all of it away: the builder concatenates the story and immediately cuts it
back to the token budget, the NPC check looks at the last 6, retrieval at the
last 4, the cursor clamp only wants a count. A turn on a 200-action adventure
read 839 KB to use ~70 KB, and grew with every turn played. app/context/
history.py serves those shapes from SQL; window_covering() measures the
actions it fetched and projects how many more it needs, fetching only the
part it does not already hold. Memorybank cursors move to position_of_index()
and settled_count()/settled_slice() — same arithmetic, no full list.
The scripting pipeline still receives the whole history per AI Dungeon's API,
and every helper reuses adventure.actions when it is already loaded, so a
scripted adventure pays what it always did and never twice.
Measured at production shape: retry tax 5.1 KB -> 0; turn 200 839 KB -> 129 KB
and flat from ~turn 50; a 200-turn playthrough 84.5 MB -> 23.0 MB; a delete
115 KB -> 5 KB.
Verified the window builds a byte-identical prompt to the full story across
budgets from 1K to 100K tokens, with and without the retry exclusion - this
is a cost change and nothing else. Cursor helpers checked against the old list
arithmetic, including after deleting a middle action. Counts are real
SELECT count(...): Query.count() wraps the entity select in a subquery, so the
SQL named every deferred column and the egress guard could not tell it apart
from a bulk fetch. 139 tests pass; the four new guards verified by sabotage.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UeQVy5bEjLhfgWNc27Efet
Three fallout bugs from keeping the retried action row alive (906ba42),
plus two long-standing cursor bugs the same investigation turned up.
Retry context leak: the row being regenerated is still attached to the
adventure, so it was replayed as established story and the model wrote a
continuation of the attempt it was meant to replace — the story visibly
blended both takes. It leaked into four places, not one: history replay,
story-card trigger matching, in-scene NPC detection, and the memory-bank
similarity query. Adds a shared context.story_actions(exclude_action_id),
threaded through build_context and retrieve_memories.
Memory holdback: a memory could summarize the just-generated turn; retry
rewrites Action.text but memory_cursor has already advanced, so the memory
was never regenerated and went on describing narration no longer in the
story. settled_story_actions() holds the newest action back one turn —
only the last action is retryable, so that makes it unreachable. The
settled list is always a prefix, so cursors stay valid and nothing is
skipped. The run_post_turn clamp deliberately still uses the full count:
clamping to settled rewinds legacy adventures a step and double-covers an
action.
Cursor bookkeeping: memory_cursor is a position into story_actions() while
Memory.source_* are Action.index values, and the two diverge as soon as
anything is deleted. Deleting a middle action slid a never-summarized
action into the covered range, skipping it forever; and pruning a memory
left the actions it covered stranded behind the cursor. Adds
note_action_removed() (called before the delete in delete_action and
undo_turn) and a rewind in prune_dangling_memories. delete_action also
now prunes at all, which it never did.
Not addressed: editing an already-summarized action still leaves its
memory stale, and the cumulative story summary can't have one fact
un-mixed from it.
117 backend tests pass, including new test_memory_settling.py (12) and
two retry-context regression tests.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UeQVy5bEjLhfgWNc27Efet