# crop-chem-docs

MCP server over ~4,000 public US row-crop pesticide / herbicide / fertilizer labels — feeding the same Drawbar farm-advisor AI as the sibling [`seed-mcp`](https://git.jpaul.io/justin/seed-mcp). The advisor calls this MCP for label rates, REI/PHI, rotation restrictions, tank-mix guidance, and active-ingredient lookups.

Built on [`docs-mcp-template`](https://git.jpaul.io/justin/docs-mcp-template) (same template lineage as seed-mcp). **In production** on trashpanda; the Drawbar advisor calls it via the `chem:` prefix.

## What's in the corpus

**4,159 indexed pages** across two complementary sources:

| Source | Pages | Notes |
|---|---|---|
| `bayer` | 91 | Bayer Crop Science US product pages — Warrant, Harness, Roundup, Liberty, Capreno, etc. Rich Next.js `__NEXT_DATA__` payload: active ingredients, label rates, MOA codes, supplemental PDFs (24c / 2EE / bulletins). robots.txt explicitly whitelists RAG indexing. |
| `epa_ppls` | 4,068 | EPA Pesticide Product Label System — every registered ag chemistry product. Authoritative source of truth for EPA reg numbers, master labels, signal words, registrant info, formulations. |

## MCP tools

Same shape as the docs-mcp-template's standard tools (see [`docs_mcp/server.py`](docs_mcp/server.py)):

| Tool | Purpose |
|---|---|
| `search_docs` | Hybrid dense + BM25 + rerank search over the label corpus, filterable by source. |
| `get_page` | Full label record by `(source, source_key)`. Returns marketing copy + extracted PDF text + sidecar metadata. |
| `list_versions` | Facet discovery (sources, EPA registrant codes, label categories). |
| `crop_chem_api_lessons` | Curated agronomy / regulatory lessons — EPA reg-number normalization, label-supersession ordering, common tank-mix gotchas. |
| Plus the template's standard `diff_versions`, `bundle_changelog`, `weekly_digest` if needed. |

## Retrieval — eval-validated

From [`eval/results/with_rerank.md`](eval/results/with_rerank.md) (35 golden queries, k=5):

| Retriever | MRR | Recall@5 | nDCG@5 | Time (s) |
|---|---|---|---|---|
| **hybrid+rerank** | **0.672** | **0.638** | **0.621** | 823 |
| bm25 | 0.544 | 0.586 | 0.524 | 5 |
| dense+rerank | 0.171 | 0.143 | 0.149 | 805 |
| hybrid-rrf | 0.114 | 0.114 | 0.108 | 8 |
| dense | 0.027 | 0.086 | 0.041 | 5 |

**Deploy config**: `HYBRID_SEARCH=true` + `RERANK_URL=http://llama-rerank:8080`.

Pattern matches what seed-mcp found independently:

1. **Dense embedding alone is essentially useless** on this corpus (MRR 0.027). Variety codes, EPA reg numbers, and active-ingredient names have no semantic neighbors — `nomic-embed-text` returns noise.
2. **Hybrid-rrf (no rerank) is worse than BM25 alone.** RRF dilutes BM25's strong ranking with dense noise. Don't ship without rerank.
3. **BM25 alone (MRR 0.544, 5 sec) is a great fallback** when the rerank sidecar is unavailable.
4. **Rerank brings the win** — `hybrid+rerank` MRR 0.672 is 23% better than BM25 alone and dominates every other configuration.

**Note on rerank in production**: through 2026-05-25 the `llama-rerank` sidecar was attached to Docker's default `bridge` network instead of `drawbar-backend_default`, so chem-mcp's `RERANK_URL=http://llama-rerank:8080` was resolving via public DNS to a random IP and connection-refusing. The MCP fell back to dense+BM25 silently. Fixed via `docker network connect drawbar-backend_default llama-rerank`. Re-running the eval is on the follow-up list; expect the deployed MRR to lift toward the lab number.

## Quick start

```bash
git clone https://git.jpaul.io/justin/crop-chem-docs.git
cd crop-chem-docs
python -m venv venv && source venv/bin/activate
pip install -r requirements.txt

# Sample-scrape to verify wiring:
python -m scrape.runner --source bayer --limit 5

# Full refresh (be polite — bayer is small, epa_ppls is hours):
python -m scrape.runner --source bayer --force
python -m scrape.runner --source epa_ppls --force

# Rebuild Chroma + BM25:
OLLAMA_URL=http://192.168.0.125:11434 PRODUCT_NAME=crop_chem \
  python -m rag.index --rebuild

# Run the eval harness:
RERANK_URL=http://localhost:18080 python -m eval.run_eval \
  --queries eval/queries.jsonl --k 5 \
  --output eval/results/baseline.md

# Local MCP server (stdio for Claude Desktop dev):
PRODUCT_NAME=crop_chem python -m docs_mcp.server --transport stdio
```

## Repo layout

```
.
├── CLAUDE.md                      # Canonical agent guide
├── PLAN.md                        # Template's 13-phase build guide
├── README.md
├── requirements.txt
├── Dockerfile
├── deploy/
│   ├── docker-compose.yml         # Drop-in compose for Drawbar
│   ├── drawbar-compose-snippet.md # Notes on the parent compose merge
│   └── rerank-docker.md           # llama-rerank service deployment
├── .gitea/workflows/
│   ├── refresh.yml                # Monthly cron: scrape + index + image push
│   └── image-only.yml             # On-demand code-only ship cycle
├── scrape/
│   ├── runner.py                  # Dispatches `--source <id>`
│   ├── changelog.py               # Reusable: --json, --history-out
│   └── sources/
│       ├── bayer.py               # cropscience.bayer.us Next.js scraper
│       └── epa_ppls.py            # EPA PPLS pagination + label PDFs
├── rag/
│   ├── embeddings.py              # nomic-embed-text via Ollama
│   ├── chunk.py                   # Chunker w/ EPA-reg-number preamble
│   ├── index.py                   # Chroma + BM25 builder
│   └── bm25.py                    # FTS5 lexical index
├── docs_mcp/
│   ├── server.py                  # FastMCP — hybrid+rerank
│   ├── lessons.md                 # Curated knowledge layer
│   └── usage.py                   # TimedCall + JSONL telemetry
├── eval/
│   ├── queries.jsonl              # 35 golden queries
│   ├── retrievers.py              # 5 named configurations
│   ├── run_eval.py                # MRR / Recall@k / nDCG@k
│   └── results/                   # Baseline + with_rerank measurements
├── scripts/
│   ├── usage_report.py
│   └── registry_gc.py             # Container registry cleanup
└── corpus/                        # Committed scrape output (CI-refreshed)
    ├── bayer/
    └── epa_ppls/
```

## Infrastructure

- **Registry**: pushes to `192.168.0.2:1234` (LAN, no CF body cap); deploys pull `git.jpaul.io/justin/crop-chem-docs:latest` (public, CF tunnel). Also tagged `:<sha12>` for rollback pinning and `:corpus-YYYY.MM.DD` for snapshot pinning.
- **Embedder pool (CI)**: 3 GPU-pinned Ollama endpoints, weighted toward `.0.125` (RTX 40-series).
- **Reranker**: shared `llama-rerank` sidecar on trashpanda's Tesla P4 (`jina-reranker-v2-base-multilingual` via llama.cpp). Same container serves crop-chem-docs and seed-mcp.
- **PRODUCT_NAME**: `crop_chem` — used in `crop_chem_docs` Chroma collection, `bm25/crop_chem_docs.db`, and the `crop_chem_api_lessons` tool name.

## Deploy mechanics

Same Watchtower auto-deploy chain as seed-mcp. On every push to `main` that touches `docs_mcp/`, `rag/`, `scrape/`, `requirements.txt`, `Dockerfile`, or `sources.json`:

1. `image-only.yml` checks out main + committed corpus
2. Rebuilds Chroma + BM25 (~few min on the GPU pool)
3. `docker build` + push three tags to the LAN registry
4. Links the package to the repo via Gitea API
5. Watchtower on trashpanda polls `:latest` every 5 min → recreates `drawbar-backend-chem-mcp-1`

Corpus refresh runs monthly via `refresh.yml`. EPA PPLS is the slow source — ~hours at 1 req/sec at full scale.

## Sibling

[`seed-mcp`](https://git.jpaul.io/justin/seed-mcp) covers the row-crop seed-variety + yield-trial side of the advisor's tool catalog. Both MCPs are docs-mcp-template clones running side-by-side on trashpanda, sharing the Ollama pool and the `llama-rerank` sidecar.

See [`CLAUDE.md`](./CLAUDE.md) for canonical sidecar schemas, the EPA reg-number normalization rules, and label-supersession ordering.