Editing a question now snapshots its previous state. The last 5 are kept — the
value is undoing a recent mistake, not an audit trail, and an uncapped history of
full question bodies grows without bound (migration a9b0c1d2e3f4).
A restore snapshots the current state first, so the restore is itself undoable.
History is gated by the same per-category grant that gates editing, so it cannot
be read by someone who could not have made the edit. The question editor shows
the versions with their dates and a Restore action.
Also added docs/TODO.md tracking everything requested and not yet delivered:
AI Mode and its citation contract, global search, study-plan editing and
articles-in-blocks, admin settings revamp, image libraries and question folders,
media management, nested article sections with references and per-section notes
and feedback, per-question notes and feedback in the runner, tutorial mode, the
per-question performance table, the Overview dashboard, systems subsystems, and
dropping "Pediatrics" as a discipline.
Tests: 6 new backend (snapshot on edit, cap at five newest-first, restore,
restore is undoable, refused without edit rights, unknown version). Full suites
green: 119 backend, 136 frontend, build clean.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PpfzbZ1QTLMeVYxM2kyq8m
Search
- Retrieval was hybrid in name only: the keyword filter was applied to the SQL
query, so results were the *intersection* of the two rankers. A question that
matched the meaning but not the literal string could never be returned. It is
now a union, fused with Reciprocal Rank Fusion (a text rank and a cosine
distance are not on comparable scales, so RRF uses only their orderings).
- Added a generated `search_vector` tsvector + GIN index, so the lexical half is
ranked full text rather than ILIKE substring matching.
- Chose Postgres + pgvector over OpenSearch/Elasticsearch: a search cluster
would add a second datastore to keep in sync and a JVM on this host, to
replace an index Postgres maintains inside the same transaction.
- Removed the keyword-only mode. It looks precise but silently drops the
question that asks the same thing in different words.
Embeddings — measured on 500 real questions, using each question's own
explanation as a paraphrase query (known answer, no hand labelling):
bge-small (local CPU, 384d) R@1 0.840 R@5 0.953 186ms/query
bge-m3 (LiteLLM proxy, 1024d) R@1 0.847 R@5 0.973 93ms/query
BGE-M3 wins on both quality and latency and needs no extra credential, since
llm.danvics.com already serves `openrouter-bge-m3`.
Three gaps this exposed, all fixed:
- Nothing recorded which model produced a stored vector, so changing models
silently mixed incomparable spaces. `embedding_model` / `embedded_at` now
stamp every vector, `GET /admin/embedding/health` reports current vs stale vs
missing, and regeneration defaults to stale-only.
- The generator read the model from env while the stamp read a Redis override,
so a vector could be labelled with a model that did not produce it. Both now
resolve through one function, with a regression test.
- Embedding at creation is best effort, and a failure left a question invisible
to semantic search forever. `retry_missing_embeddings` runs every 15 minutes
via Celery beat and backfills missing or stale rows.
- Query embeddings are cached in Redis per model, so typing is not a network
round-trip per keystroke.
`dimensions` is only sent to OpenAI's embedding-3 family; BGE-M3 rejects it.
Tests: 8 new backend tests (union not intersection, fusion ordering, per-ranker
failure degradation, provenance stamping, stale/missing accounting, generator
and stamp agreement). Full suites green: 95 backend, 127 frontend, build clean.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014yhHB8Pc7oQqyqn2Vo9DXA
Key points on questions link into article sections (AMBOSS-style) with samples; difficulty tagging with builder/bank filters; adaptive session algorithm prefers unanswered questions then recycles older incorrect ones, weakest categories first with damping; question create/edit is now admin/educator only; expired exams no longer auto-submit on resume; exam suspend messaging updated. Migrations k4f5a6b7c819, l5a6b7c8d920, m6a7b8c9d031. 63 backend and 97 frontend tests pass.
Questions support an explanation per option, edited in the question dialog and shown in study feedback. Keys must match current options. Migration j3e4f5a6b708. 60 backend and 95 frontend tests pass.
Recovery snapshot of the existing worktree before the Orthobullets-inspired revamp. Includes explanation images, classification snapshots, quiz visibility/resume fixes, quiz codes, TTS options and bot formatting. Secret heuristic and Python syntax checks passed; not a release or full behavioral validation.
- Fully decouple course quizzes from main quiz system (hidden from
dashboard stats, history, search, results page)
- Course quiz results show "Back to Course" instead of retake/delete
- Add allow_review toggle for course creators to control answer review
- Show quiz title on course page, hide pool size from students
- Add course thumbnails to browse cards
- Replace passlib with bcrypt directly (compatible with existing hashes)
- Add HIBP breached password warnings on register/reset/change password
- Add CLI management tools (reset-password, set-role, stats, etc.)
- Fix quiz PATCH endpoint: ownership check instead of moderator-only
- Add max_length validation on course/module/lesson titles
- Fix score display bug on results page (0 of N when review disabled)
- Fix question count on course quiz start (show per-attempt, not pool)
- Improve suspend warning for timed course quizzes with max attempts
- Clean up validation error messages (show "Invalid email" not Pydantic dump)
- Add DDL migration for allow_review column
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- teach.py: use _proxy_model() + pass api_key/api_base from settings (fixes LiteLLM provider error for openrouter/bedrock models)
- teach.py: accept model_id in ChatRequest so frontend can select model
- main.py: remove titan-embed-v2 from general seed, auto-delete legacy entry on startup
- main.py: kill stale idle-in-transaction DB connections at startup to prevent DDL lock hangs
- main.py: set lock_timeout=10s on DDL connection as fast-fail safety net
- TeachChat.jsx: fetch /teach/models, show selector dropdown in header when >1 model available
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Question sharing (edits now propagate):
- quiz_question_links junction table: quizzes reference questions, not own copies
- Existing questions migrated to junction (idempotent ON CONFLICT DO NOTHING)
- from-bank and from-category create quiz by adding junction links (no copying)
- Editing a question via QuizEditPage or bank Edit modal updates the ONE record
visible in all quizzes that reference it
- Delete from quiz: only deletes Question record if no other quiz references it
- quiz_service: fixed position counter (was using len() incorrectly, now enumerate)
- question.quiz_id renamed to source_quiz_id in Python (DB column still quiz_id)
- All attempts/quizzes/search code updated to use junction helper or source_quiz_id
Bug fixes:
- PostgreSQL en_US.utf8 collation B-tree index corruption on users.email
Fixed by ALTERing column to COLLATE "C" in migration + immediate repair
- get_current_user now blocks unverified users on ALL endpoints (403 + X-Unverified header)
api/client.js intercepts X-Unverified=true and auto-logs out to /login
- Search (quiz + bank): correct_answer and explanation now included in matching_questions
so study modals work correctly
- Keyword search: order_by updated to use source_quiz_id
- Bulk category: changed from PATCH with body array to POST with Pydantic body
(fixes null category_id removal)
- Question bank: edit button added, answer highlighting removed from list view
- QuestionBankPage: Keyword/Semantic/Hybrid search toggle
- Login: login error message stays visible (removed immediate reload)
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
Architecture:
- Questions are primary objects in a bank, tagged with question categories
- QuestionCategory is a separate taxonomy from QuizCategory (different concepts)
- Extraction → questions added to bank, optionally tagged to a question category
- Quizzes can be created from: individual question selection, question category, or PDF extraction
Backend:
- QuestionCategory model + question_categories table
- question_category_id column on questions table (nullable, SET NULL on delete)
- GET/POST/PATCH/DELETE /api/question-categories/
- POST /api/question-categories/{id}/create-quiz — create quiz from all questions in a category
- PATCH /api/questions/{id}/category — assign single question to category
- PATCH /api/questions/bulk-category — assign multiple questions at once
- GET /api/questions/bank?category_id=&uncategorized= — filter by category
- QuizCreate schema now accepts question_category_id for extraction
- quiz_service.create_quiz_from_section accepts question_category_id param
Frontend:
- DocumentDetailPage: Add to Bank Category dropdown in Quiz Settings (optional)
Labels extracted questions with the selected category on creation
- QuestionBankPage: full rewrite
- Category chips for filtering (All / Uncategorized / named categories)
- Create category button inline
- Checkbox multi-select with bulk category assignment
- Create Quiz modal: choose from selected questions OR all from a category
- Each question shows its category badge and quiz source
- Study modal with instant answer feedback
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
- FastAPI backend with JWT auth, roles (admin/moderator/user)
- PDF upload (up to 500MB) with streaming, PyMuPDF text extraction
- ChromaDB vectorization per page with metadata
- LiteLLM AI question extraction from PDF (not generation)
- Image extraction from PDF pages, graceful fallback
- Quiz modes: timed (countdown timer) + learning (answers shown inline)
- Page-by-page question navigation with dot navigator
- TTS endpoint using LiteLLM (Google Vertex / OpenAI voices)
- Admin dashboard: AI model management per task, user role management
- Moderator role: upload PDFs, create sections, generate quizzes
- Spaced repetition reminders via SMTP email (SM-2 intervals)
- APScheduler daily reminder jobs
- Celery + Redis for background PDF processing
- React frontend with all pages
- Docker Compose deployment (nginx + backend + celery + redis)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
