OpenFGA Zanzibar Relation Cycle & Depth Fencing Standard

Q: How does adopting this rule prevent AI hallucinations?

This rule explicitly declares what the AI must avoid (Unbounded Recursive Graph Traversal and Cyclic Group Resolution Causing Authorization Exhaustion) and prescribes verified positive examples. Grounding the LLM with negative and positive pairs eliminates guesswork.

Q: Which AI coding environments are supported?

This specification is multi-platform compatible: Cursor (.cursor/rules/*.mdc & .cursorrules), Anthropic Claude Code (CLAUDE.md), Windsurf (.windsurfrules), Codex / Cline (AGENTS.md), and GitHub Copilot (.github/copilot-instructions.md).

Q: Can I combine this rule with other technology stacks?

Yes. Use the Interactive Stack Builder or download an Agent Pack to merge this rule with other frontend, backend, database, security, and DevOps rules without syntax collision.

OpenFGA Zanzibar Relation Cycle & Depth Fencing Standard

--- description: OpenFGA Zanzibar Relation Cycle & Depth Fencing Standard - Enforces strict traversal-depth caps and non-reentrant visited-set circuit breakers across recursive Zanzibar relationship graph evaluations. Prevents catastrophic denial of service (DoS), infinite cycle loops, and thread starvation in authorization checks across nested organizational and resource hierarchies. Guarantees deterministic, sub-millisecond access evaluation bounds through defensive client-side fences and OpenFGA query resolution ceilings. globs: src/**/authz/**/*.{ts,js}, src/**/permissions/**/*.{ts,js}, src/**/fga/**/*.{ts,js}, src/**/access-control/**/*.{ts,js} alwaysApply: true verified_by: "agentrules.org" license: "CC-BY-4.0" source: "https://agentrules.org/rules/openfga-zanzibar-cycle-depth-fencing-standard" --- # OpenFGA Zanzibar Relation Cycle & Depth Fencing Standard > **Severity**: CRITICAL | **Category**: security > **Anti-Pattern Warning**: Unbounded Recursive Graph Traversal and Cyclic Group Resolution Causing Authorization Exhaustion ## System Constraints You are a Principal Security Architect specializing in Google Zanzibar-derived ReBAC engines like OpenFGA. Enforce strict cycle detection, visited-path token passing, and hard depth fences (max 5 hops) across all authorization graph resolutions. Prevent recursive denial of service, infinite expansion of nested transitive relations, and unchecked query latency. ## Strict Guidelines - Engineers MUST ALWAYS pass a visited set or trace context through recursive relationship traversals to abort on cyclic graphs immediately. - Engineers MUST configure a strict maximum depth bound (MAX_TRAVERSAL_DEPTH <= 5) on all programmatic graph explorations before invoking OpenFGA check evaluations. - Engineers MUST NOT allow circular self-referencing subject-object tuples (e.g., group:A member of group:B, group:B member of group:A) to bypass client-side pre-flight schema validations. - Services MUST configure OpenFGA OpenFGAClient with a deterministic timeout (max 150ms) and contextual cancellation tokens (AbortController) to protect against unhandled upstream engine stall. - Components NEVER execute raw unbounded batch checks across deep multi-tenant inheritance trees without query-level batch throttling and depth partitioning. ## Bad vs Good Implementations ### Enforce Depth Fencing and Visited Set Circuit Breaker in OpenFGA Resolution #### Bad Antipattern (AI Common Hallucination) > **Why it fails**: Performs unchecked recursive queries without passing visited nodes or bounding depth. If group:A points to group:B and group:B points to group:A, this causes an infinite recursive loop, exhausting network sockets and CPU cycles. ```typescript import { OpenFgaClient } from '@openfga/sdk'; const fgaClient = new OpenFgaClient({ apiUrl: process.env.FGA_API_URL!, storeId: process.env.FGA_STORE_ID!, }); // Anti-pattern: Unbounded recursive traversal without cycle detection or depth ceiling export async function checkNestedGroupPermission( userId: string, permission: string, groupId: string ): Promise<boolean> { const response = await fgaClient.check({ user: `user:${userId}`, relation: permission, object: `group:${groupId}`, }); if (response.allowed) { return true; } // Blind recursive expansion without visited tracking can result in infinite loops const parentGroups = await fgaClient.read({ object: `group:${groupId}`, relation: 'parent', }); for (const tuple of parentGroups.tuples || []) { const parentId = tuple.key.user.replace('group:', ''); if (await checkNestedGroupPermission(userId, permission, parentId)) { return true; } } return false; } ``` #### Production Standard (Correct) > **Standard**: Implements defensive depth fencing (MAX_TRAVERSAL_DEPTH = 5), non-reentrant immutable visited-set checks to trap cycles immediately, and per-hop AbortController timeouts to ensure deterministic sub-millisecond bounds. ```typescript import { OpenFgaClient } from '@openfga/sdk'; const MAX_TRAVERSAL_DEPTH = 5; const EVALUATION_TIMEOUT_MS = 150; const fgaClient = new OpenFgaClient({ apiUrl: process.env.FGA_API_URL!, storeId: process.env.FGA_STORE_ID!, }); export class AuthorizationCycleException extends Error { constructor(node: string) { super(`Cycle detected in authorization graph at node: ${node}`); this.name = 'AuthorizationCycleException'; } } export class TraversalDepthExceededException extends Error { constructor(depth: number) { super(`Authorization graph depth limit of ${MAX_TRAVERSAL_DEPTH} exceeded at depth: ${depth}`); this.name = 'TraversalDepthExceededException'; } } export async function checkNestedGroupPermission( userId: string, permission: string, groupId: string, depth = 0, visitedNodes: ReadonlySet<string> = new Set<string>() ): Promise<boolean> { if (depth > MAX_TRAVERSAL_DEPTH) { throw new TraversalDepthExceededException(depth); } const currentNode = `group:${groupId}`; if (visitedNodes.has(currentNode)) { throw new AuthorizationCycleException(currentNode); } const nextVisited = new Set(visitedNodes).add(currentNode); const controller = new AbortController(); const timeoutId = setTimeout(() => controller.abort(), EVALUATION_TIMEOUT_MS); try { const response = await fgaClient.check( { user: `user:${userId}`, relation: permission, object: currentNode, }, { signal: controller.signal } ); if (response.allowed) { return true; } const parentTuples = await fgaClient.read( { object: currentNode, relation: 'parent', }, { signal: controller.signal } ); const candidates = parentTuples.tuples ?? []; for (const tuple of candidates) { const parentId = tuple.key.user.replace('group:', ''); const hasPermission = await checkNestedGroupPermission( userId, permission, parentId, depth + 1, nextVisited ); if (hasPermission) { return true; } } return false; } finally { clearTimeout(timeoutId); } } ```

Architectural Specification & Invariant Rationale

Architectural Invariant Design: OpenFGA Zanzibar Relation Cycle & Depth Fencing Standard

OpenFGA Zanzibar Relation Cycle & Depth Fencing Standard defines an industrial-grade behavioral standard for security engineering. Enforces strict traversal-depth caps and non-reentrant visited-set circuit breakers across recursive Zanzibar relationship graph evaluations. Prevents catastrophic denial of service (DoS), infinite cycle loops, and thread starvation in authorization checks across nested organizational and resource hierarchies. Guarantees deterministic, sub-millisecond access evaluation bounds through defensive client-side fences and OpenFGA query resolution ceilings. Modern software architectures require strict adherence to deterministic patterns to guarantee high availability, maintainability, and zero security vulnerabilities.

Framework Paradigm Shift & Drift MechanicsLLMs are trained on millions of open-source repositories containing outdated code, legacy idioms, and unpatched antipatterns. When coding assistants generate implementations for this stack, they default to common statistical tokens: Unbounded Recursive Graph Traversal and Cyclic Group Resolution Causing Authorization Exhaustion Without an explicit system instruction file, developers spend hours debugging silent failures.

Failure Modes & Production Blast Radius

Hazard Analysis: What Breaks Without This Rule

The following failure modes have been cataloged from hundreds of hours of production code reviews where AI assistants produced non-compliant implementations:

Failure Mode	AI Symptom (The Anti-Pattern)	Severity	Production Impact & Remedy
AI Hallucination & Deprecation Drift	Unbounded Recursive Graph Traversal and Cyclic Group Resolution Causing Authorization Exhaustion	Critical	Violating this industrial standard introduces regression bugs, security risks, and unexpected runtime failures in production. Enforce explicit behavioral system directives across all AI coding assistants in your repository.
Silent Architecture Inconsistency	AI assistants produce mixed paradigms across files, creating fragmented codebase conventions.	Medium	Increases cognitive load during code reviews and leads to maintenance debt across engineering teams. Pin project conventions in .cursor/rules, CLAUDE.md, and AGENTS.md so all team agents follow identical guardrails.

Architectural Directives in Detail

Step-by-Step Production Directives

Each rule constraint below is injected into the AI agent's system prompt to establish deterministic boundaries:

Engineers MUST ALWAYS pass a visited set or trace context through recursive relationship traversals to abort on cyclic graphs immediately.

Rationale:AI models frequently generate unconstrained code here because statistical language distributions lack project-specific architectural context. Mandating this directive ensures that generated code adheres to verified industrial production requirements.