Tier 1 check-format was picking images.zip over testmini.parquet,
causing wrong columns (image/label) and broken VLM mapping.
Also log first VLM conversion failure instead of swallowing silently.
Instead of downloading the full dataset and then slicing, use
streaming mode to only fetch the rows needed (up to slice_end + 1)
when a manual dataset slice is configured.
startswith(prefix) could match unrelated split variants whose names
extend the selected file's prefix (e.g. model-Q8_0-v2-00001-of-...).
Now builds an exact regex from the chosen file's base prefix and shard
total so only true siblings are downloaded.
Substring matching (e.g. "Q8_0" in filename) could match superset
variants like "IQ8_0", causing wrong quantizations to be downloaded.
Now uses word-boundary regex for variant matching and discovers split
shards by shared filename prefix rather than treating all variant
matches as shards.
start_training() cherry-picks kwargs into a config dict but was missing
is_embedding, so config.get("is_embedding", False) in worker.py always
returned False and embedding training never ran.
LlamaCppBackend.load_model() only downloaded the first matching GGUF
file. For split models (e.g. 7B Q8_0 with 3 shards), llama-server
needs all shards present. Now collects and downloads all matching files.
Add end-to-end embedding/sentence-transformer training pipeline using
FastSentenceTransformer, SentenceTransformerTrainer, and
MultipleNegativesRankingLoss with BatchSamplers.NO_DUPLICATES.
Backend:
- Add is_embedding_model() detection via HF tags + pipeline_tag
- Add /check-embedding/ API route and EmbeddingCheckResponse
- Extend derive_model_type() to return "embeddings"
- Add _run_embedding_training() in worker.py with progress callbacks,
stop handling, LoRA (task_type=FEATURE_EXTRACTION), and model saving
- Add is_embedding field to TrainingStartRequest and ModelDetails
- Add YAML configs for 5 models: all-MiniLM-L6-v2, bge-m3,
embeddinggemma-300m, gte-modernbert-base, Qwen3-Embedding-0.6B
Frontend:
- Wire isEmbeddingModel flag through store, API types, and mappers
- Force packing=false, train_on_completions=false, warmup_ratio=0.03
- Hide packing and train_on_completions checkboxes for embedding models
- Auto-set modelType to "embeddings" from backend model_type response
- Pass 1: clearer definition of "conversational" vs non-conversational,
constrained dataset_type to specific enum values
- Pass 2: much more explicit worked examples with step-by-step reasoning,
added "skip" role for metadata columns, stronger reminder at end that
all-user is wrong
- Pass 3: returns raw text instead of JSON for cleaner system prompts,
removed system message to give model more freedom
The advisor now only assigns columns to user/assistant roles and
generates a system prompt. Templates (user_template, assistant_template)
are removed entirely — the LLM was frequently putting all columns in
user or copying actual data values into templates.
Column values are now used directly as message content, grouped and
concatenated by role. This is simpler, more robust, and prevents the
class of bugs where the advisor generates bad template content.
Derive a single model_type string ("text" | "vision" | "audio" | "embeddings")
from existing is_vision and audio_type detection, so the frontend doesn't have
to infer modality from scattered boolean flags.
The LLM was putting all columns in user_template (e.g. summarization
dataset had both document AND summary as user input). Fixed by:
- Reframed system message: explicitly states user=INPUT, assistant=OUTPUT
- Added 4 concrete correct examples (summarization, NLI, translation, QA)
showing exactly how to split columns
- Added "NEVER put the output/target column in the user template" rule
- Added sanity check: if assistant_template has no column placeholders,
reject the result and fall back to simple classification
Pass 3 now sees the label mapping from Pass 2 (e.g. "0 = does not follow,
1 = follows, 2 = entailed") so the generated system prompt can explain
what each label value means. Also bumped to 2-4 sentences to give room
for the label descriptions.
Pass 1: Classify dataset type (unchanged)
Pass 2: Generate user/assistant templates + label mapping + column roles
(system_prompt removed from this pass to keep it focused)
Pass 3: Generate system prompt (only for non-conversational datasets)
- Dedicated pass with focused prompt that sees the templates from Pass 2
- Skipped entirely for conversational datasets
- Produces specific, task-relevant system prompts
- System prompt is now optional — LLM only generates one when the task
is ambiguous from the data alone (persona, domain, format constraints)
- Sanitize system_prompt extraction (handle literal "null" string)
- Show system prompt, user template, and assistant template in the
advisor notification banner so user can see exactly what was generated
- Templates displayed in monospace with labeled sections
The LLM was bad at scoring its own conversion quality — rejecting good
Pass 2 output (score 5/10 for a perfectly usable conversion). Instead:
- Remove Pass 3 entirely (saves ~0.4s and one inference call)
- Trust Pass 2 output and return it to the user
- Build notification from Pass 1 classification info instead
- User can always adjust mapping via dropdowns if they disagree
- Reject advisor result when Pass 3 scores < 6 or is_acceptable=false,
falls back to simple column classification instead of using bad output
- Improved Pass 2 prompt: explicit rules for label_mapping completeness,
{column_name} vs {column_name_name} for mapped labels, column_roles
must match which template uses them
- Build suggested_mapping from ALL template-referenced columns (not just
first match per role) — fixes hypothesis being dropped from SNLI mapping
- Guard against LLM returning literal string "null" for revised_system_prompt
- Always show AI Assist button when available, even when mapping looks complete
- Handle dict columns (e.g. squad answers) by extracting text instead
of raw repr()
- Handle list columns by joining or extracting single value
- Catch ValueError in .format() calls (stray { } in column data)
- Add missing json import to dataset_utils.py
Non-conversational HF datasets (e.g. stanfordnlp/snli) were naively mapped
column→role, producing poor training results. The AI Assist button now runs
a 3-pass advisor using Qwen 7B that:
1. Fetches the HF dataset card/README to understand the dataset purpose
2. Classifies the dataset type and determines if conversion is needed
3. Generates a system prompt, user/assistant templates with {column}
placeholders, and label mappings (e.g. 0→entailment)
4. Validates the conversion quality (score ≥7/10 required)
Architecture: advisor metadata flows as __-prefixed keys in
custom_format_mapping (e.g. __system_prompt, __user_template,
__assistant_template, __label_mapping). The existing _apply_user_mapping()
detects these keys and routes to template-based conversation construction.
No __ keys = existing simple mode (backwards compatible).
Backend: upgraded llm_assist.py (7B default, multi-pass advisor,
HF card fetching), extended API models, added _apply_template_mapping()
to dataset_utils.py.
Frontend: extended store with advisor state fields, wired AI Assist
to store templates/system prompt, inject __ metadata in training request,
show advisor notification banner in mapping card.
LlamaCppBackend.load_model() and precache_helper_gguf() only downloaded
the first matching GGUF file. For split models (e.g. 7B Q8_0 with 3
shards), llama-server needs all shards present. Now collects and
downloads all matching files.
Move LLM-assisted column mapping from silent /check-format automation
to an explicit "AI Assist" button in the dataset mapping dialog. This
makes the feature transparent and user-controlled.
- Remove llm_classify_columns() from check_dataset_format() (heuristic-only)
- Remove auto-save suggested_mapping from use-training-actions.ts
- Add POST /api/datasets/ai-assist-mapping endpoint (receives preview
samples from frontend, no dataset re-loading needed)
- Add AiAssistMappingRequest/Response models
- Add aiAssistMapping() frontend API function
- Add Sparkles AI Assist button to DatasetMappingCard with loading state
- Wire up handleAiAssist handler in dataset-preview-dialog.tsx
- Frontend auto-saves suggested_mapping into datasetManualMapping when
check-format returns requires_manual_mapping=false, so the mapping
flows to training via custom_format_mapping (no redundant AI calls)
- Backend returns meaningful warning when column detection fails
(LLM-generated or static fallback) for both text and VLM datasets
- /check-format endpoint merges check_dataset_format warnings with
existing URL-based image detection warnings
