data-science-python-railguard-available

A Cursor coding rule for safer data-science work in Python scripts and notebooks. It covers loading, previewing, transforming, and exporting data while protecting personally identifiable information such as names, emails, and phone numbers.

In plain words
What is it for?
Use it when writing pandas-based data loading and export code, previewing datasets, masking or removing sensitive columns, enforcing column types, and avoiding `eval` or `exec` on unvalidated input.
Why use it?
It reduces accidental exposure of sensitive data and discourages executing untrusted expressions while leaving detailed input-validation rules to a separate rule.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/brighton-labs/railguard-cursor-coding/data-science-python-railguard-available
Clone the repo
git clone --depth 1 https://github.com/brighton-labs/railguard-cursor-coding

Made for: Cursor.

Per session 739 This file is loaded in full into every session.
When invoked 739 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00739 $0.00739
Opus 5 $0.00369 $0.00369
Sonnet 5 $0.00148 $0.00148
Haiku 4.5 $0.00074 $0.00074

Measured 2d ago against content hash ff86fb2bff2d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

data-science-python-railguard-available scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/data-science-python-railguard-available.mdc · 90 lines

How it starts

The opening of the file, as written. The whole thing — 90 lines — stays where its author put it; the contents beside it link to each section on GitHub.


description: Guide the LLM to generate secure, privacy-conscious data science code in notebooks and Python scripts. Defers input validation to .cursor/rules/input-validation.mdc while enforcing safe loading, export, and transformation of data. globs: ["/*.ipynb", "/*.py"] alwaysApply: true

Overview

This rule supports data analysts and scientists working in Python (e.g., Jupyter, Colab, VSCode notebooks) by:

  • Enforcing safe data previews and exports
  • Preventing accidental leakage of personally identifiable information (PII)
  • Deferring all structured input validation logic to:

    .cursor/rules/railguard-input-validation.mdc
    (which uses the RAILGUARD Framework for secure reasoning and enforcement)


Safe Data Handling

  • Use pandas.read_csv() and read_excel() with dtype=... to enforce schema.
  • Always drop or mask sensitive fields before using .head(), .sample(), or .plot().
  • Never use eval(), exec(), pd.eval() or query() on raw data or unvalidated user inputs.
  • When exporting data, verify and exclude all PII fields.

Default PII fields to remove:

PII_FIELDS = ["email", "full_name", "ssn", "ip", "dob", "phone", "address"]
  • Always log sanitized export filenames using logging, not print().
  • Prefer versioned, structured export paths (e.g., exports/cleaned_data_v1.csv).

Cross-Reference: Validation Logic

Input validation, schema enforcement, sanitization, and secure reasoning are handled globally in:

.cursor/rules/railguard-input-validation.mdc

This ensures:

  • Protection against malformed files, unexpected schema, or poisoned input
  • Step-by-step generation reasoning (RAILGUARD pillars)
  • Enforcement of redlines (e.g., avoiding eval, ensuring schema is present)
  • Behaviorally aware, explainable code generation across file types

Example: Secure Data Load + Export

import pandas as pd
import logging

PII_FIELDS = ["email", "ssn", "address", "full_name"]

# Load CSV with enforced column types
df = pd.read_csv("customers.csv", dtype={"id": str, "email": str})

# Drop sensitive fields
df_clean = df.drop(columns=PII_FIELDS, errors="ignore")

# Preview non-sensitive columns only
print(df_clean[["id", "signup_date"]].head())

# Export with logging
output_path = "exports/customers_clean_v1.csv"
df_clean.to_csv(output_path, index=False)
logging.info(f"Exported sanitized data to {output_path}")

Read the full file on GitHub · 90 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 90 lines · 739 tokens per session scan A ff86fb2bff2d

Subscribe to this mod's changes

data-science-python-railguard-available is a cursor rule published in the GitHub repository brighton-labs/railguard-cursor-coding (13 stars, last pushed 1y ago), licensed MIT. It adds 739 tokens to every session, about $0.0037 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.