# RAG + VectorDB — Global Fix Map
🏥 Quick Return to Emergency Room
> You are in a specialist desk.
> For full triage and doctors on duty, return here:
>
> - [**WFGY Global Fix Map** — main Emergency Room, 300+ structured fixes](https://github.com/onestardao/WFGY/blob/main/ProblemMap/GlobalFixMap/README.md)
> - [**WFGY Problem Map 1.0** — 16 reproducible failure modes](https://github.com/onestardao/WFGY/blob/main/ProblemMap/README.md)
>
> Think of this page as a sub-room.
> If you want full consultation and prescriptions, go back to the Emergency Room lobby.
This hub covers **typical retrieval bugs caused by vector databases and embeddings**.
Use this page if your RAG pipeline looks fine but answers keep drifting, citations don’t match, or hybrid retrievers underperform.
Every page here is a guardrail with copy-paste recipes and acceptance targets.
---
## Orientation: what each page means
| Fix Page | What it solves | Typical symptom |
|----------|----------------|-----------------|
| [metric_mismatch.md](./metric_mismatch.md) | Distance metric mismatch (cosine vs L2 vs dot) | High similarity numbers but wrong meaning |
| [normalization_and_scaling.md](./normalization_and_scaling.md) | Missing normalization or scaling issues | Embeddings with larger norms dominate |
| [tokenization_and_casing.md](./tokenization_and_casing.md) | Tokenizer or casing drift | Same text embeds differently across runs |
| [chunking_to_embedding_contract.md](./chunking_to_embedding_contract.md) | Chunking not aligned with embedding model | Citations cut mid-sentence or incoherent snippets |
| [vectorstore_fragmentation.md](./vectorstore_fragmentation.md) | Over-fragmented stores | Retrieval pulls incomplete, scattered sections |
| [dimension_mismatch_and_projection.md](./dimension_mismatch_and_projection.md) | Embedding and index dimension mismatch | Runtime errors or silent drop of vectors |
| [update_and_index_skew.md](./update_and_index_skew.md) | Index not refreshed after updates | Old sections keep showing up |
| [hybrid_retriever_weights.md](./hybrid_retriever_weights.md) | Hybrid weighting not tuned | BM25+ANN underperforms single retriever |
| [duplication_and_near_duplicate_collapse.md](./duplication_and_near_duplicate_collapse.md) | Redundant entries collapse signal | Top-k filled with near-identical chunks |
| [poisoning_and_contamination.md](./poisoning_and_contamination.md) | Malicious or noisy vectors | Hallucinations, unsafe content retrieval |
---
## When to use this folder
- Your answers look **semantically wrong** even though top-k similarity looks high.
- Citations point to the wrong section or cannot be verified.
- Hybrid retrieval underperforms vs single retriever.
- Index seems “healthy” but recall/coverage stays low.
---
## Core acceptance targets
- ΔS(question, retrieved) ≤ 0.45
- Coverage of target section ≥ 0.70
- λ_observe convergent across 3 paraphrases
- E_resonance flat on long windows
---
## FAQ for newcomers
**Why do we need these fixes if VectorDBs are mature?**
Because RAG pipelines often break not at the infra level but at the **semantic boundary**. Even if FAISS, Milvus, or Pinecone run fine, the *contracts* between embedding, chunking, and retrieval are fragile.
**What is metric mismatch and why is it deadly?**
If your index uses `L2` but embeddings were trained for `cosine`, the “closest” neighbors are meaningless. This is the single most common RAG failure.
**Why do duplicates matter so much?**
If your corpus has many repeated sentences, the retriever fills top-k with clones. The LLM sees no diversity and hallucinates.
**Is poisoning really a real-world issue?**
Yes. Even a single malicious doc can bias retrieval. This page shows how to detect and quarantine them without retraining the whole pipeline.
---
## 60-Second Fix Checklist
1. **Lock metrics and analyzers**
One embedding model per field. One distance metric. Same analyzer for read/write.
2. **Enforce snippet contracts**
Require `{snippet_id, section_id, source_url, offsets, tokens}`.
→ See [data-contracts](https://github.com/onestardao/WFGY/blob/main/ProblemMap/data-contracts.md)
3. **Tune hybrid retrievers**
Keep candidate lists from BM25 and ANN. Detect query splits.
→ See [rerankers](https://github.com/onestardao/WFGY/blob/main/ProblemMap/rerankers.md)
4. **Cold-start fences**
Block traffic until index hash and embedding version match.
→ See [bootstrap-ordering](https://github.com/onestardao/WFGY/blob/main/ProblemMap/bootstrap-ordering.md)
5. **Observability**
Log ΔS and λ. Alert if ΔS ≥ 0.60.
---
### 🔗 Quick-Start Downloads (60 sec)
| Tool | Link | 3-Step Setup |
|------|------|--------------|
| **WFGY 1.0 PDF** | [Engine Paper](https://github.com/onestardao/WFGY/blob/main/I_am_not_lizardman/WFGY_All_Principles_Return_to_One_v1.0_PSBigBig_Public.pdf) | 1️⃣ Download · 2️⃣ Upload to your LLM · 3️⃣ Ask “Answer using WFGY + ” |
| **TXT OS (plain-text OS)** | [TXTOS.txt](https://github.com/onestardao/WFGY/blob/main/OS/TXTOS.txt) | 1️⃣ Download · 2️⃣ Paste into any LLM chat · 3️⃣ Type “hello world” — OS boots instantly |
---
### Explore More
| Layer | Page | What it’s for |
| --- | --- | --- |
| Proof | [WFGY Recognition Map](/recognition/README.md) | External citations, integrations, and ecosystem proof |
| Engine | [WFGY 1.0](/legacy/README.md) | Original PDF based tension engine |
| Engine | [WFGY 2.0](/core/README.md) | Production tension kernel and math engine for RAG and agents |
| Engine | [WFGY 3.0](/TensionUniverse/EventHorizon/README.md) | TXT based Singularity tension engine, 131 S class set |
| Map | [Problem Map 1.0](/ProblemMap/README.md) | Flagship 16 problem RAG failure checklist and fix map |
| Map | [Problem Map 2.0](/ProblemMap/rag-architecture-and-recovery.md) | RAG focused recovery pipeline |
| Map | [Problem Map 3.0](/ProblemMap/wfgy-rag-16-problem-map-global-debug-card.md) | Global Debug Card, image as a debug protocol layer |
| Map | [Semantic Clinic](/ProblemMap/SemanticClinicIndex.md) | Symptom to family to exact fix |
| Map | [Grandma’s Clinic](/ProblemMap/GrandmaClinic/README.md) | Plain language stories mapped to Problem Map 1.0 |
| Onboarding | [Starter Village](/StarterVillage/README.md) | Guided tour for newcomers |
| App | [TXT OS](/OS/README.md) | TXT semantic OS, fast boot |
| App | [Blah Blah Blah](/OS/BlahBlahBlah/README.md) | Abstract and paradox Q and A built on TXT OS |
| App | [Blur Blur Blur](/OS/BlurBlurBlur/README.md) | Text to image with semantic control |
| App | [Blow Blow Blow](/OS/BlowBlowBlow/README.md) | Reasoning game engine and memory demo |
If this repository helped, starring it improves discovery so more builders can find the docs and tools.
[](https://github.com/onestardao/WFGY)