Data extract

Data Extract

Pull structured data out of documents and into a clean .xlsx + an audit report. The counterpart to data-tidy: tidy cleans data that's already roughly tabular; extract locates and pulls data from document-shaped sources (forms, multi-table PDFs, scans). Both share one engine, so extracted data is normalised and reported the same way.

Self-sufficient & local engine. No other toolkit needed. All processing — including OCR — happens on your machine: no cloud OCR, no external APIs, no third-party uploads. Note the AI agent driving the skill does send whatever it reads into its context to your AI provider; "never leaves the machine" is not claimed. See ../../PRINCIPLES.md#data-handling--pii-policy.

Shared engine. The cleanup primitives live at the plugin-root scripts/ (dataclean.py, ingest.py); this skill's scripts/extract.py adds them to the path.

Which mode?

You have…	Mode	Use
a form / certificate / confirmation (label: value)	fields	extract_fields → one record per doc
a document with one or more tables	table	list_tables → get_table → the rows
many documents, same shape (e.g. 30 confirmations)	fields, batched	one record each → fields_to_table → one .xlsx

Workflow

0 — Intent (ask up front)

What's the document, and which fields / which table do you want out? For forms, the field list (name + the labels to look for + type). For tables, the target columns. This pins extraction to a target — economical, no guessing.

1 — Set up (run from the skill directory)

First, check for an existing runner/card for this doc type (see Reuse below) — if one exists, follow that flow instead of re-deriving. Otherwise:

import sys, pathlib
sys.path.insert(0, str(pathlib.Path("../../scripts").resolve()))   # shared engine
import extract, dataclean      # extract, dataclean, ingest all live in ../../scripts

Run from the skill directory (skills/data-extract/). The ../../scripts path resolves to the toolkit-root scripts/ where extract.py, dataclean.py and ingest.py live.

2 — Extract

Form / key-value — one record per document:

FIELDS = [
  {"name": "Investor",   "labels": ["investor", "name of investor"], "type": "text"},
  # mixed-currency batch: keep the code beside the amount with code_target (amount + code)
  {"name": "Commitment", "labels": ["commitment", "amount"], "type": "currency",
   "code_target": "Commitment ccy"},
  {"name": "Close date", "labels": ["close date", "closing"], "type": "date"},
]
record, flags = extract.extract_fields("subscription.pdf", FIELDS)

For a currency field, add code_target to keep the detected code in its own key on the record (mirrors the tidy recipe) — essential for mixed-currency batches (GBP / SGD / USD in one run) so the amount isn't delivered stripped of its code. Give an expected currency instead (or as well) only when the documents are single-currency and you want a bare $ resolved to it. extract_fields finds Label: value / Label[tab]value / Label value / Label .... value (dotted leader), and the next-line layout (label alone, value on the line below — common on confirmations/certificates), stopping at the next field's label so it won't grab a neighbouring label. Converts by type (amounts as exact Decimal; bare $ ambiguous → give expected currency) and flags anything not found or uncertain (kept raw, never invented). Genuinely 2-D box/grid layouts still need table mode instead.

Tables — pick, then pull:

for c in extract.list_tables("report.pdf"):   # {page, index, rows, cols, preview}
    ...                                        # show candidates, let the user choose
rows = extract.get_table("report.pdf", page=1, index=0)

Scanned docs — handled automatically: a page with no text layer falls back to local Tesseract OCR (ingest.ocr_available() to check). OCR use is noted in the ingest/read_text note as lower-fidelity; it is not tagged per row.

Image inputs — charts, table screenshots, diagrams

When the source is a chart, table screenshot, UI capture, or diagram image (.png / .jpg / .jpeg / .gif / .webp / .bmp), use scripts/image_extract.py to extract structured data via a vision model — not Tesseract (Tesseract mangles tables and cannot read chart data points):

python scripts/image_extract.py chart.png -o extracted.xlsx
python scripts/image_extract.py ./screenshots/ -o batch.xlsx   # one sheet per image + combined

Classification + prompts: references/image-prompts.md. Requires a vision-capable OpenAI-compatible endpoint (VISION_API_KEY / OPENAI_API_KEY, optional VISION_BASE_URL / VISION_MODEL). Without a key the script exits clearly — it does not silently fall back to OCR. Results are cached by file+prompt hash; large images (>5MB / >2048px) are compressed before the API call.

PowerPoint decks (.pptx) — ingest.read_any / ingest.read_pptx extracts tables from all slides (same row contract as .docx). Slide titles/bullets are summarised in the ingest note, not mixed into the table rows. Image-only slides are flagged for manual review or vision-model extraction. Legacy .ppt is not supported — convert to .pptx first.

3 — Normalise, output, report

For tables, pass the rows through the shared recipe just like tidy (dataclean.apply_recipe). For batched forms:

header, rows = extract.fields_to_table(records, extract.field_columns(FIELDS))
dataclean.write_xlsx(header, rows, "extracted.xlsx")
print(extract.render_fields_report(records, flags_list))

extract.field_columns(FIELDS) gives the column order and inserts each currency field's code_target column right after its amount — so the workbook keeps amount + code. (A plain [f["name"] for f in FIELDS] would drop the code columns.) Deliver the .xlsx + the report (unfound / verify flags).

4 — Triage: a reusable runner, or just deliver?

Default: just deliver the result (the .xlsx + report) and stop — for a one-off or simple extraction, don't create runner/card files; they'd only be clutter.

Emit a self-contained reuse bundle only when it's worth it:

• Recurring — the same doc type will come again (monthly statements, batches of the same confirmation), or the user says they'll reuse it; or
• Complex — many fields / fiddly label matching / multi-table, so re-deriving next time is genuinely costly.

When it's borderline, ask the user. If yes:

dataclean.emit_runner("[working-folder]", "subscription-confirmation", "extract", FIELDS)
# -> extract_subscription-confirmation.py + .md card + copies of dataclean/ingest/extract

It deploys the runner (.py, spec baked in), the card (.md), and a copy of the engine into that folder — so the bundle runs without the plugin installed. Keep them together (e.g. in your synced or shared file store, beside the docs). Pass the real working-folder path, not the skill folder.

Reuse — when a runner already exists (verify FIRST, then run)

If a extract_[doctype].{py,md} exists for this document, do not blind-run it — slight drift (a renamed label, an added column) would otherwise pass silently:

1. Read the .md card — note the expected fields/labels.
2. Inspect the current source (ingest.read_text / open it).
3. Compare to the card's Expected source.
4. Match → run it: python extract_[doctype].py [doc...] [-o out.xlsx] — deterministic, ~no reasoning tokens. The runner also self-checks and warns on missing fields.
5. Drifted → adapt: update the spec for the change and regenerate the runner (emit_runner), then run. Don't run a stale spec.

Safety

• Human-in-the-loop — show what was extracted and the flags; let the user verify before it's relied on. A draft extraction for review, not a certified dataset.
• Never invents — an unfound field is blank + flagged; OCR/ambiguous values are flagged.

OCR (scanned documents)

Local Tesseract only — never a cloud OCR, so no third-party service ever sees your documents. External binary (not pip): python ../../scripts/envcheck.py probes for it. Without it, digital PDFs, Word and .msg still work; only image/scanned pages need it. Windows install: winget install UB-Mannheim.TesseractOCR (admin rights; on a managed machine, ask IT to deploy).

Files

• ../../scripts/extract.py (shared) — extract_fields, fields_to_table, list_tables, get_table, render_fields_report; reuses dataclean + ingest; --self-test.
• ../../scripts/dataclean.py (shared) — the engine + emit_runner (reuse runners/cards).
• ../../scripts/ingest.py (shared) — source adapters incl. read_text + local-OCR.
• scripts/image_extract.py — vision-model extraction for chart / table / UI / diagram images; parse_markdown_table, batch → styled .xlsx.
• references/extraction-guide.md — field-list spec, table selection, extract-vs-tidy, reuse.
• references/image-prompts.md — image-type → prompt strategy table.
• examples/sample_subscription_confirmation.pdf — a synthetic form to try extract_fields.

Principles

Behavioural charter: ../../PRINCIPLES.md — drafts not advice, never invent, honesty and calibration, plain speech, action boundary.

Data handling

The engine runs on your machine and makes no network calls for PDF/form/table extraction (local OCR only). Image/chart extraction (image_extract.py) is the exception: it sends the (possibly compressed) image to a user-configured vision API — treat that like any other external tool under PRINCIPLES.md#data-handling--pii-policy (de-identify first when the image holds PII or confidential figures). The documents are often sensitive or confidential (subscription confirmations, statements, certificates name parties and amounts). Never send a document, its text, or OCR of it to an external or third-party tool unless the user has explicitly chosen vision extraction for an image; the extracted .xlsx stays in your synced or shared file store. Be aware the AI agent driving this skill sends whatever it reads into its context to your AI provider, as in any AI-assisted work. Full rule: ../../PRINCIPLES.md#data-handling--pii-policy. (No external connector — files are local paths in your synced or shared file store.)

Feedback

Have an improvement or found a bug in this skill? Capture it with the toolkit's shared feedback format — ../../CONTRIBUTING.md#skill-feedback-format — so it reaches the skill author consistently (skill name, what you did, expected vs actual, severity, suggestion). Save it as a .txt file (feedback_[skill]_[date].txt) and hand it to the user to file (e.g. in your synced or shared file store) — manual, no fixed destination; fix in scope if asked.

Requirements & mode

Pre-screen: see ../../README.md#mode--environment-compatibility and run python ../../scripts/envcheck.py. Needs Python + PyMuPDF (PDF), openpyxl (output); pdfplumber (optional — preferred for messy / borderless PDF tables), python-docx for .docx, python-pptx for .pptx, extract_msg for .msg; local Tesseract only for scanned-document OCR (degrades cleanly without it). Image/chart extraction needs a vision-capable OpenAI-compatible API endpoint + key (Pillow, requests, pandas optional helpers) — without it image_extract.py exits clearly and does not fall back to Tesseract.