AGENTS.md Template: PCI Compliant System Design for AI Coding Agents

Overview

Direct answer: This AGENTS.md Template governs PCI compliant system design for AI coding agents, enabling both single-agent workflows and multi-agent orchestration with strict data handling, segmentation, key management, and auditability. It provides a project-level operating manual to codify roles, controls, and escalation paths for PCI-aligned AI systems.

The template is designed to support both single-agent execution and multi-agent orchestration (agent handoffs, cross-agent collaboration, and governance) while keeping cardholder data protected and within a minimized PCI scope. Use this to bootstrap a repeatable, auditable design process that enforces least-privilege access, tokenization, encryption, and traceable decision logs.

When to Use This AGENTS.md Template

When building a PCI DSS-compliant AI system that handles or touches cardholder data (even in tokenized form) and requires strict data governance.
When you need a defined agent roster with clear responsibilities and escalation paths for PCI-related risk management.
When you must enforce data flow segmentation, tokenization, and encryption in transit and at rest across multiple agents.
When you want auditable handoffs between planner, implementer, reviewer, and tester with traceable decision logs.
When you need a repeatable deployment and change-management process with human review for high-risk changes.

Copyable AGENTS.md Template

# AGENTS.md

Project Role: PCI compliant system design lead, security architect, and orchestrator for AI coding agents.

Agent roster and responsibilities:
- Planner: defines PCI scope, data flow, tokenization, segmentation; ensures CDE minimization.
- Implementer: implements PCI controls in code and CI/CD; ensures encryption, key mgmt, secrets handling.
- Reviewer: security/compliance reviewer; checks PCI DSS mapping and audit readiness.
- Tester: performs security tests (SAST/DAST, fuzzing), validates PCI controls in pipelines.
- Researcher: gathers PCI guidance, threat modeling inputs, and vendor docs.
- Domain Specialist: payments domain expert ensuring alignment with real-world card processing rules.

Supervisor or orchestrator behavior:
- The orchestrator coordinates tasks, enforces policy, maintains a decision log, and triggers escalation for high-risk states.
- Enforces tool governance, memory, and traceability across agents; blocks non-compliant actions and requires sign-offs before progression.

Handoff rules between agents:
- Preconditions: approved plan, artifact readiness, and risk assessment.
- Artifacts: design documents, data-flow diagrams, threat models, test results.
- Acceptance criteria: satisfies PCI controls, passes security checks, and is signed off by the reviewer.
- Context: pass memory state, data dictionaries, and relevant logs to the next agent; version all artifacts.
- Sign-off: ensure the receiving agent acknowledges acceptance before proceeding.

Context, memory, and source-of-truth rules:
- Source of truth: central data dictionary, PCI policy repo, and threat model repository.
- Memory: ephemeral per run; logs and artifacts go to secure storage with immutability guarantees.

Tool access and permission rules:
- Restricted tool access by role; secrets vault access limited to authorized agents; no PAN storage in logs.
- Secrets rotation: rotate keys and credentials on a fixed cadence or after incident triggers.

Architecture rules:
- PCI-compliant architecture with network segmentation, encryption in transit and at rest, and tokenization where possible.
- No direct PAN storage; use tokenized references for processing and logs.

File structure rules:
- Keep files under a single PCI-designated workspace with clear separation between config, code, and policy.

Data, API, or integration rules:
- Data minimization; tokenization for data in-flight; no PAN in logs or outputs unless strictly required and encrypted.
- Use approved payment gateways and cryptographic standards (e.g., TLS 1.2+, AES-256).

Validation rules:
- Validate PCI mapping coverage; run security tests; verify tokenization and data-flow restrictions.

Security rules:
- Enforce least privilege; MFA for access; audit all actions; encrypt secrets; monitor for anomalies.

Testing rules:
- Unit tests for PCI edge-cases; integration tests for data flows; security tests; regression tests for handoffs.

Deployment rules:
- Use canary or blue/green deployments; require approvals for changes touching PCI scope; maintain rollback plans.

Human review and escalation rules:
- Escalate to security/compliance owners for high-risk changes; maintain an escalation contact list.

Failure handling and rollback rules:
- If a control fails, halt affected pipelines, roll back to last known good state, and trigger incident review.

Things Agents must not do:
- Do not store PAN or unencrypted card data; do not bypass PCI controls; do not hide audit logs; do not alter PCI scope without proper approval.

Recommended Agent Operating Model

Roles and decision boundaries are defined to maintain PCI compliance across single-agent and multi-agent workflows. Planner decides scope and risk posture; Implementer translates controls into automation; Reviewer validates compliance; Tester confirms security readiness; Researchers gather guidance; Domain Specialists ensure payments domain fidelity. Escalation paths are in place for high-risk decisions and policy exceptions.

Recommended Project Structure

ai-pci-system-design/
  config/
  docs/
  agents/
    planner/
    implementer/
    reviewer/
    tester/
    researcher/
    domain/
  workflows/
  memory/
  logs/
  pipelines/
  src/
  tests/
  README.md

Core Operating Principles

Strict data governance and PCI scope management.
Clear separation of duties and least-privilege access.
Auditable agent decisions and traceable handoffs.
Tokenization and encryption for data in transit and at rest.
Explicit human review for high-risk changes.

Agent Handoff and Collaboration Rules

Planner → Implementer: validate scope, data flow, and controls.
Implementer → Reviewer: present implementation details and PCI mappings for validation.
Reviewer → Tester: provide test plan aligned to PCI controls.
Researcher → Domain Specialist: corroborate payments-domain requirements and risk factors.
Domain Specialist → Planner: feedback on feasibility and risk mitigation.

Tool Governance and Permission Rules

Commands affecting PCI scope require approval from the Planner and Reviewer.
Edits to policy/config are logged and require sign-off.
Secrets access strictly limited; rotate on schedule and after incidents.
Production changes must pass security review and risk assessment.

Code Construction Rules

Avoid logging PAN; use tokenized references and pseudonyms in all code and logs.
Follow PCI-compliant cryptographic practices; use approved libraries and standards.
Implement input/output validation; fail closed on unknown data formats.
Avoid hard-coded credentials; fetch from secure vaults at runtime.

Security and Production Rules

Enforce MFA and least privilege for all access to PCI components.
Encrypt data in transit with TLS 1.2+ and at rest with AES-256 or equivalent.
Monitor and alert on anomalous behaviors; retain logs securely for forensics.
Maintain incident response runbooks and rollback capabilities.

Testing Checklist

PCI mapping presence and accuracy.
Security testing: SAST/DAST, threat modeling verification.
Data flow validation with tokenization and CDE boundaries.
End-to-end workflow tests with rollbacks enabled.
Audit trail integrity checks.

Common Mistakes to Avoid

Storing PAN or unencrypted data in logs or artifacts.
Bypassing escalation for PCI risk events.
Ambiguity in handoff artifacts and acceptance criteria.
Neglecting threat modeling for PCI data paths.

FAQ

What is the purpose of this AGENTS.md Template: PCI Compliant System Design?

It provides a copyable operating manual to guide PCI compliant AI agent workflows, ensuring secure data handling, tokenization, and auditable handoffs across a multi-agent system.

How does multi-agent orchestration help PCI compliance?

It enforces separation of duties, auditable handoffs, and centralized policy enforcement, reducing risk to cardholder data across complex AI-driven processes.

How are secrets and keys managed in this workflow?

Secrets are stored in a dedicated vault with strict access controls; keys are rotated regularly and managed by a hardware security module (HSM) or equivalent service.

What happens if a security violation is detected?

The orchestrator triggers an incident response workflow, halts affected paths, and initiates rollback and stakeholder notification.

What are the handoff rules between planner, implementer, and reviewer?

Handoffs require validated artifacts, passing of memory state, explicit acceptance criteria, and signed-off transitions before the next agent proceeds.

Target User

Use Cases