forge-prep

Data readiness toolkit for Mistral Forge — audit, clean, and prepare enterprise data for custom model training.

forge-prep is an independent open-source project. It is not affiliated with, endorsed by, or sponsored by Mistral AI.

42% of enterprise teams spend more than half their time maintaining and organizing data rather than using it productively (Futurum 1H 2026). Forge is an incredible platform, but most enterprises can't use it because their data isn't ready.

forge-prep bridges that gap.

The output below is the real, unedited result of running forge-prep audit examples/sample-corpus/ against the demo corpus checked into this repo — clone it and run the same command to reproduce it exactly.

$ forge-prep audit examples/sample-corpus

╔════════════════════════════════════════════════════╗
║                 forge-prep v0.1.1                  ║
║      Data Readiness Toolkit for Mistral Forge      ║
╚════════════════════════════════════════════════════╝

Auditing: examples/sample-corpus

═══ Forge Readiness Score ═══

  ████████░░░░░░░░░░░░░░░░░░░░░░  27.8/100  Grade: F
  Not ready — corpus needs fundamental restructuring before any model training.

  Corpus Summary
  Files:    10
  Size:     0.0 MB
  Tokens:   ~2,873  (uncertain — range 2,206–3,530, see docs/methodology.md)
  Dupes:    1
  PII hits: 6

  Dimension Breakdown
  Volume               █░░░░░░░░░░░░░░  10.0  2,873 tokens (0 MB) — insufficient for any Forge training stage. Token count is
  Quality              ███░░░░░░░░░░░░  20.0  Pervasive quality issues (40% flag rate). Major filtering needed.
  Deduplication        ██████░░░░░░░░░  45.0  1 duplicates (10.0%) — significant dedup required.
  Privacy              █░░░░░░░░░░░░░░  10.0  Widespread PII (6 files, 60.0%). Critical: scrub before any training.
  Language Focus       ████████████░░░  80.0  Bilingual corpus — consider if both languages are needed for your domain.
  Format Consistency   ██████████░░░░░  70.0  4 file formats. Consider standardizing to .txt or .jsonl for Forge.

Reports saved:
  Markdown: forge-prep-output/forge_readiness_report.md
  JSON:     forge-prep-output/forge_readiness_report.json

The scoring weights and grade bands above are heuristics chosen by this project's author, not requirements published by Mistral — see docs/methodology.md for the full formula and the reasoning behind it, and docs/limitations.md for what the tool does not catch before you rely on it.

What It Does

Both commands support --format {text,json} and --quiet for scripting, and audit supports --fail-under N to make the exit code CI-friendly (forge-prep audit ./data --fail-under 70 exits 1 if the score is below 70).

Exit codes

A corpus with zero supported files never produces a score — a directory of .png/.exe files, or an empty directory, prints a distinct "No supported files found" message (files present, files skipped, top unsupported extensions, and the supported-extension list) instead of a fake grade, and JSON output is {"status": "no_supported_files", "score": null, ...}. Consumers parsing the JSON should always check score for null before using it — never assume a numeric score means the corpus was actually assessed.

Supported extensions

.txt .md .mdx .csv .json .jsonl .xml .html .htm .py .js .ts .yaml .yml .rst .tex .log .tsv .sql .sh .adoc .org .toml .ini .cfg

Use --include-ext .foo,.bar to scan additional extensions without waiting on a release, and --exclude-ext .log,.sh to skip extensions that are in the default set but not relevant to your corpus. Both flags work on audit and clean.

Audit Dimensions

• Volume — Is there enough data for Forge pre-training vs. fine-tuning? Token counts are estimated from character counts with a per-file-type multiplier, not run through a real tokenizer. For file types where that estimate's held-out error exceeds ±25% (currently CSV/JSONL), the report shows a range instead of a single number — see docs/methodology.md for exactly how much to trust it.
• Quality — Short files, low text density, high repetition, encoding issues
• Deduplication — Exact content duplicates detected via SHA-256 hashing
• Privacy — PII detection across the entire file (email, phone, IP, credit card, SSN, IBAN, French NIR), each validated with a checksum or context check to cut down on false positives — see docs/limitations.md for what it can't see
• Language Focus — Multilingual corpus detection with automatic language identification
• Format Consistency — File type distribution and standardization recommendations

PII scanning covers the full file by default (in bounded, overlapping chunks — never the whole file in memory at once). Use --pii-scan-limit BYTES to cap the scan per file for very large corpora; any file the limit truncates is flagged pii_scan_truncated: true in the report and called out with a warning, so a partial scan is never silently reported as "clean." Use --ip-mode {public,all,off} to control whether private/loopback IP ranges count as PII (default: public, meaning private ranges are ignored since they're not personal data on their own).

Credit-card detection rejects published test card numbers (Stripe, Visa, Mastercard, Amex, etc.), low-entropy digit runs (padding, sequential runs), matches inside a longer hex/UUID value, and — by default — matches inside dense/minified/vendored content; use --strict-pii to see everything, unfiltered. This was validated against a full clone of vercel/next.js: 7 confirmed false positives (Stripe's own test cards, JS numeric constants, a null GUID) before the fix, 0 after — see docs/methodology.md for the details and docs/limitations.md for exactly what's being suppressed.

Cleaning Pipeline

$ forge-prep clean examples/sample-corpus --output ./forge-ready/

═══ Cleaning Results ═══

  Processed:  10 files
  Kept:       7
  Removed:    3
  Deduped:    1
  PII scrubs: 5 files (25 replacements)
  Size:       0.0 MB → 0.0 MB (40.0% reduction)

The cleaner:

• Removes exact-content duplicates
• Replaces PII with typed placeholders ([EMAIL_REDACTED], [PHONE_REDACTED], etc.), using the exact same validated detection logic as audit (they share one code path in forge_prep/pii.py, so they can't disagree)
• Filters files below quality thresholds (too short, low text density, high repetition) — thresholds are configurable via --min-chars, --min-text-density, and --max-repetition-ratio
• Outputs a clean, Forge-compatible directory structure

Redaction here is pseudonymisation, not anonymisation — see docs/limitations.md before treating cleaned output as safe to share without a lawful basis.

Installation

# From source (zero external dependencies)
git clone https://github.com/satoshi-kris/forge-prep.git
cd forge-prep
pip install -e .

# Then run
forge-prep audit ./your-data/

Zero external dependencies. The core toolkit uses only Python 3.10+ stdlib. No pip install wall, no version conflicts, no ML frameworks required.

Output

Every audit produces:

• forge_readiness_report.md — Human-readable Markdown report
• forge_readiness_report.json — Machine-readable JSON for CI/CD integration (forge-prep audit ./data --format json prints the same JSON straight to stdout, no file needed)

Architecture

forge-prep/
├── forge_prep/
│   ├── __init__.py          # Package exports
│   ├── auditor.py           # Corpus scanning & file-level analysis
│   ├── cleaner.py           # Dedup, PII scrub, quality filter
│   ├── pii.py                # Shared PII detection + validation (used by auditor and cleaner)
│   ├── scorer.py            # 0–100 readiness scoring engine
│   ├── report.py            # Markdown + JSON report generation
│   └── cli.py               # Command-line interface (argparse)
├── examples/
│   └── sample-corpus/       # Demo enterprise corpus
├── docs/
│   ├── methodology.md       # Scoring formula, weights, and their provenance
│   └── limitations.md       # What the PII detector does not catch
├── pyproject.toml
└── README.md

Why This Exists

Mistral Forge gives enterprises the power to train custom models on their own data. But there's a prerequisite most announcements skip: the data has to be ready.

The typical enterprise corpus contains:

• Duplicated documents across departments
• PII scattered through emails, tickets, and CRM exports
• Low-quality files (auto-generated logs, boilerplate, placeholder docs)
• Mixed languages without intentional multilingual strategy
• Inconsistent formats that require different parsing pipelines

forge-prep is the pre-flight checklist before you commit Forge compute budget. It tells you exactly where your data stands, what to fix, and whether fine-tuning or full pre-training is the right call for your corpus size.

Roadmap

Nothing below is built yet — none of it is claimed elsewhere in this README.

• Near-duplicate detection (MinHash/LSH over shingles) — exact-hash dedup catches almost nothing in real corpora where documents differ by a header or footer
• JSONL training-format converter (chat, instruction, completion schemas)
• GitHub Action wrapping --fail-under / --format json with a job summary
• PDF/DOCX text extraction (optional [docs] extra)
• Report diffing (forge-prep diff old.json new.json) to track corpus health over time
• Optional real tokenizer (forge-prep[tokens], mistral-common or tiktoken) in place of the word-count heuristic
• Interactive dashboard for visual exploration of a report — not built, and not shipped in this repo today
• Forge API connector (direct upload of clean corpus)

License

Apache 2.0

Built by Kris — M.S. Data Science & Business Intelligence, EDC Paris Business School (2026)