FSI Compliance Checker

Overview

Maps a concrete change (code diff, architecture design, IaC, pipeline config) to the specific controls it touches in financial services compliance frameworks — PCI-DSS v4.0 for payment card data and MAS TRM for Singapore-regulated institutions — and reports gaps with actionable remediation. This is engineering-level compliance triage: it helps teams catch violations before audit, but it does not replace a qualified assessor (QSA) or the institution's compliance function. Say so in every report.

When to Use This Skill

• Use when a change touches payment card data (PAN, CVV, track data) and needs a PCI-DSS check
• Use when reviewing changes at a Singapore-regulated financial institution against MAS TRM expectations
• Use when someone asks "is this compliant", "does logging this violate PCI", or requests a banking-regulation review of a diff, design, or Terraform change
• Do NOT use for generic security review (no framework involved), GDPR/SOC2/HIPAA (out of bundled scope), or legal advice

How It Works

Step 1: Select the framework

Load only the reference file(s) the engagement needs:

| Situation | Load | |-----------|------| | Payment card data is stored, processed, or transmitted | pci-dss.md | | Singapore-regulated financial institution (bank, insurer, capital markets, major payment institution) | mas-trm.md | | Both apply (e.g. Singapore bank handling cards) | Both files | | Other jurisdictions/frameworks (SOX, GDPR, HKMA, APRA) | State they are out of scope; offer general secure-engineering review instead |

If the user hasn't said which applies, ask one question: what data does the change touch, and is the institution Singapore-regulated?

Step 2: Scope the change

Identify what the diff/design actually touches: data elements (card data? customer PII? credentials?), trust boundaries, environments (production? DR?), and third parties.

Step 3: Assess applicable controls

Select the applicable controls from the loaded reference file(s) — typically 5-15 controls, not the whole framework. List what you ruled out and why (one line each) so the scoping is auditable. Assess each as Compliant / Gap / Needs evidence (can't tell from the artifact — name the evidence required).

Step 4: Report

Every Gap gets: the control ID, what's wrong in this specific change, concrete remediation, and severity (Critical = violation involving live regulated data; High = control absent; Medium = control partial/undocumented).

markdown
# Compliance Review: [change title]
**Frameworks:** [PCI-DSS v4.0 / MAS TRM 2021] · **Date:** [YYYY-MM-DD]
**Scope:** [what was reviewed: files, design doc, pipeline]
> Engineering triage only — not a substitute for QSA assessment or the compliance function.

## Data & Boundary Analysis
- Data elements touched: [e.g. PAN (masked), customer NRIC, none]
- Environments/boundaries: [e.g. CDE-adjacent service, public API]

## Findings
| # | Control | Status | Severity | Finding | Remediation |
|---|---------|--------|----------|---------|-------------|
| 1 | [PCI 3.5.1] | Gap | Critical | [specific issue in this change] | [specific fix] |

## Ruled Out (not applicable)
- [Control area] — [one-line reason]

## Evidence Needed
- [Control]: [what artifact would demonstrate compliance]

Step 5: Offer story conversion

Offer to turn findings into backlog items with the control ID in each story for traceability.

Examples

Example 1: Logging review

User: "Is this PCI-DSS compliant: we log the full request body of card authorization calls for debugging?"

Skill: Loads pci-dss.md → Critical findings against 3.3.1 (CVV must never be stored post-authorization — logs are storage), 3.4.1 (PAN display masking), 3.5.1 (PAN unreadable at rest); remediation: remove the log line or apply a field-allowlist redaction filter; flags downstream log-pipeline scoping (10.3.x); QSA disclaimer included.

Example 2: Cloud migration

User: "Our Singapore bank is moving the customer notification service to a cloud region in another country. MAS TRM implications?"

Skill: Loads mas-trm.md → reviews against §11.5 (cloud: due diligence, data residency, exit strategy), flags the MAS Outsourcing Guidelines as a related instrument, asks what customer data the service touches before rating severity.

Common FSI Engineering Triggers

Changes that almost always have compliance impact — check proactively when they appear in a diff:

• Logging statements near payment or authentication flows (PAN/CVV must never be logged; MAS TRM requires security event logging — both directions matter)
• New data stores or caches receiving customer or card data (encryption at rest, retention, residency)
• Authentication/session changes (MFA requirements, session timeout, credential storage)
• New third-party SDKs or API integrations (outsourcing/vendor controls, data flows leaving the boundary)
• Infrastructure changes touching network segmentation, security groups, or public exposure
• CI/CD changes that alter who/what can deploy to production (change management, segregation of duties)

Guardrails

• Cite control IDs precisely (e.g. "PCI-DSS 8.3.6", "MAS TRM 9.1.1") so findings are traceable in audit tooling; the bundled reference files carry the ID schemes.
• Severity discipline: don't inflate. A missing comment is not a Critical; unencrypted PAN at rest is.
• When the change is compliant, say so affirmatively per control — "no findings" plus the checked-control list is a useful audit artifact.
• Never output real card numbers, even as examples; use the standard test PANs (e.g. 4111 1111 1111 1111) when illustrating.
• Read-only: this skill reviews and reports; it never modifies code, infrastructure, or configuration.

Limitations

• Covers only the bundled PCI-DSS v4.0 and MAS TRM engineering summaries; other frameworks or local policy overlays need separate review.
• Provides engineering triage, not legal advice, QSA assessment, or formal compliance sign-off.
• Requires concrete evidence such as diffs, designs, IaC, logs, or control artifacts; incomplete evidence should be marked Needs evidence.
• The bundled references are concise control maps, not substitutes for reading the official standards.

Credits

Adapted from timwukp/agent-skills-best-practice (MIT), where the skill ships with evals and a documented 4-layer test methodology (see the repo's TESTING.md).