feat(P02): backend-enriched tier, chaos engineering, prioritization — IDEATE-04,05,06,09,10

---ci---
phase: 2
milestone: v0.10
status: execute
decisions:
  - id: D-087
    decision: All 6 innovative features in v1 (pattern mining, drift detection, layer inversion, cross-project, chaos, spec)
    rationale: User wants bleeding-edge; all uniquely differentiated
    confidence: 0.82
requirements:
  covered:
    - IDEATE-04
    - IDEATE-05
    - IDEATE-06
    - IDEATE-09
    - IDEATE-10
---/ci---

- IDEATE-04: Verification layer inversion (structural, behavioral, security, quality missing detection)
- IDEATE-05: Architectural drift detection (documented vs actual component comparison)
- IDEATE-06: Spec-driven improvement (ambiguity detection, missing category detection)
- IDEATE-09: Backend-enriched analysis (prioritization, novel suggestions, action plans)
- IDEATE-10: Chaos engineering ideation (backend unavailable, requirement change, coverage drop)
- Deduplicated type exports: IdeationSource/Idea/etc now in types/ideation.ts
- 538 tests passing

src/core/ideation.test.ts

@@ -2,7 +2,8 @@ import * as fs from "node:fs";
 import * as path from "node:path";
 import * as os from "node:os";
 import { IdeationAgent } from "../agents/ideation-agent.js";
-import { IdeationEngine, resetIdeaCounter, Idea } from "../core/ideation.js";
+import { IdeationEngine, resetIdeaCounter } from "../core/ideation.js";
+import { Idea, IdeationAction, DEFAULT_IDEATION_CONFIG } from "../types/ideation.js";
 
 describe("IdeationAgent", () => {
   let tempDir: string;
@@ -244,4 +245,86 @@ describe("IdeationEngine", () => {
       expect(results.every((r) => r.addedToRequirements || r.addedToRoadmap)).toBe(true);
     });
   });
+
+  describe("Phase 2: Backend-enriched and chaos", () => {
+    let tempDir: string;
+
+    beforeEach(() => {
+      resetIdeaCounter();
+      tempDir = fs.mkdtempSync(path.join(os.tmpdir(), "ciagent-p2-test-"));
+    });
+
+    afterEach(() => {
+      fs.rmSync(tempDir, { recursive: true, force: true });
+    });
+
+    it("runBackendEnriched prioritizes mechanical findings", () => {
+      const engine = new IdeationEngine(tempDir);
+      const mechanicalIdeas: Idea[] = [
+        {
+          id: "IDEATE-01",
+          source: "uncovered_requirement",
+          category: "coverage",
+          title: "Missing test",
+          rationale: "No test file",
+          confidence: 0.7,
+          actions: ["add_test"],
+          tier: "mechanical",
+        },
+        {
+          id: "IDEATE-02",
+          source: "escalation_pattern",
+          category: "security",
+          title: "Security issue",
+          rationale: "Repeated escalation",
+          confidence: 0.8,
+          actions: ["add_security_pattern"],
+          tier: "mechanical",
+        },
+      ];
+
+      const enriched = engine.runBackendEnriched(mechanicalIdeas);
+      expect(enriched.length).toBeGreaterThanOrEqual(2);
+      const prioritizedIdeas = enriched.filter((i) => i.source === "uncovered_requirement" || i.source === "escalation_pattern");
+      expect(prioritizedIdeas.length).toBeGreaterThanOrEqual(2);
+      for (const idea of prioritizedIdeas) {
+        expect(idea.tier).toBe("backend-enriched");
+      }
+    });
+
+    it("runBackendEnriched adds novel suggestions for missing categories", () => {
+      const engine = new IdeationEngine(tempDir);
+      const mechanicalIdeas: Idea[] = [
+        {
+          id: "IDEATE-01",
+          source: "uncovered_requirement",
+          category: "coverage",
+          title: "Cover this",
+          rationale: "Missing",
+          confidence: 0.7,
+          actions: ["add_test"],
+          tier: "mechanical",
+        },
+      ];
+
+      const enriched = engine.runBackendEnriched(mechanicalIdeas);
+      const novelIdeas = enriched.filter((i) => i.source === "improvement_pattern");
+      expect(novelIdeas.length).toBeGreaterThanOrEqual(1);
+    });
+
+    it("generateChaosScenarios uses default scenarios when enabled", () => {
+      const engine = new IdeationEngine(tempDir);
+      const chaosIdeas = engine.generateChaosScenarios();
+
+      expect(chaosIdeas.length).toBe(3);
+      expect(chaosIdeas.every((i) => i.source === "chaos_scenario")).toBe(true);
+      expect(chaosIdeas.every((i) => i.category === "chaos")).toBe(true);
+      expect(chaosIdeas.every((i) => i.tier === "backend-enriched")).toBe(true);
+      expect(chaosIdeas.every((i) => i.confidence >= 0.5)).toBe(true);
+      const titles = chaosIdeas.map((i) => i.title);
+      expect(titles.some((t) => t.includes("backend"))).toBe(true);
+      expect(titles.some((t) => t.includes("requirement"))).toBe(true);
+      expect(titles.some((t) => t.includes("coverage"))).toBe(true);
+    });
+  });
 });

src/core/ideation.ts

@@ -3,112 +3,18 @@ import * as path from "node:path";
 import { execSync } from "node:child_process";
 import { CIAgentFiles } from "./ciagent-files.js";
 import { GitContext } from "./git-context.js";
-
-export type IdeationSource =
-  | "uncovered_requirement"
-  | "repeated_lesson"
-  | "low_confidence_decision"
-  | "escalation_pattern"
-  | "compound_pattern"
-  | "partial_requirement"
-  | "gap_in_coverage"
-  | "improvement_pattern"
-  | "architecture_drift"
-  | "verification_inversion"
-  | "spec_ambiguity"
-  | "spec_contradiction"
-  | "spec_missing"
-  | "external_signal"
-  | "cross_project_lesson"
-  | "chaos_scenario";
-
-export type IdeationCategory =
-  | "security"
-  | "quality"
-  | "architecture"
-  | "coverage"
-  | "improvement"
-  | "spec"
-  | "chaos";
-
-export type IdeationAction =
-  | "add_requirement"
-  | "update_architecture"
-  | "update_roadmap"
-  | "fix_documentation"
-  | "add_test"
-  | "add_security_pattern"
-  | "refactor"
-  | "new_milestone_phase";
-
-export type IdeationTier = "mechanical" | "backend-enriched" | "cross-project";
-
-export interface Idea {
-  id: string;
-  source: IdeationSource;
-  category: IdeationCategory;
-  title: string;
-  rationale: string;
-  confidence: number;
-  relatedReq?: string;
-  actions: IdeationAction[];
-  tier: IdeationTier;
-}
-
-export interface IdeationResult {
-  project: string;
-  milestone: string;
-  ideas: Idea[];
-  summary: IdeationSummary;
-}
-
-export interface IdeationSummary {
-  total: number;
-  accepted: number;
-  skipped: number;
-  by_category: Record<string, number>;
-  by_tier: Record<string, number>;
-}
-
-export interface IdeationConfig {
-  enabled: boolean;
-  categories: IdeationCategory[];
-  confidence_threshold: number;
-  max_ideas: number;
-  external_signals: {
-    npm_audit: boolean;
-    osv_advisories: boolean;
-    dependency_staleness: boolean;
-  };
-  cross_project: {
-    enabled: boolean;
-    similarity_weight: number;
-  };
-  chaos: {
-    enabled: boolean;
-    scenarios: string[];
-  };
-}
-
-export const DEFAULT_IDEATION_CONFIG: IdeationConfig = {
-  enabled: true,
-  categories: ["security", "quality", "architecture", "coverage", "improvement"],
-  confidence_threshold: 0.6,
-  max_ideas: 20,
-  external_signals: {
-    npm_audit: true,
-    osv_advisories: true,
-    dependency_staleness: true,
-  },
-  cross_project: {
-    enabled: false,
-    similarity_weight: 0.5,
-  },
-  chaos: {
-    enabled: true,
-    scenarios: ["backend_unavailable", "requirement_change", "test_coverage_drop"],
-  },
-};
+import { loadConfig } from "./config.js";
+import {
+  IdeationSource,
+  IdeationCategory,
+  IdeationAction,
+  IdeationTier,
+  Idea,
+  IdeationResult,
+  IdeationSummary,
+  IdeationConfig,
+  DEFAULT_IDEATION_CONFIG,
+} from "../types/ideation.js";
 
 let ideaCounter = 0;
 
@@ -815,6 +721,172 @@ export class IdeationEngine {
     return ideas;
   }
 
+  runBackendEnriched(mechanicalIdeas: Idea[], context?: string): Idea[] {
+    resetIdeaCounter();
+    const enriched: Idea[] = [];
+
+    const prioritized = this.prioritizeMechanicalFindings(mechanicalIdeas);
+    enriched.push(...prioritized);
+
+    const novelSuggestions = this.suggestNovelImprovements(mechanicalIdeas);
+    enriched.push(...novelSuggestions);
+
+    const chaosScenarios = this.generateChaosScenarios();
+    enriched.push(...chaosScenarios);
+
+    return enriched.slice(0, DEFAULT_IDEATION_CONFIG.max_ideas);
+  }
+
+  private prioritizeMechanicalFindings(mechanicalIdeas: Idea[]): Idea[] {
+    const categoryPriority: Record<string, number> = {
+      security: 1.0,
+      coverage: 0.9,
+      architecture: 0.8,
+      quality: 0.7,
+      improvement: 0.6,
+      spec: 0.5,
+      chaos: 0.4,
+    };
+
+    const sourceBoost: Record<string, number> = {
+      escalation_pattern: 0.15,
+      repeated_lesson: 0.1,
+      uncovered_requirement: 0.1,
+      compound_pattern: 0.08,
+      low_confidence_decision: 0.05,
+      architecture_drift: 0.05,
+      verification_inversion: 0.03,
+    };
+
+    return mechanicalIdeas
+      .map((idea) => ({
+        ...idea,
+        confidence: Math.min(
+          idea.confidence + (categoryPriority[idea.category] || 0) * 0.1 + (sourceBoost[idea.source] || 0),
+          1.0
+        ),
+        tier: "backend-enriched" as IdeationTier,
+      }))
+      .sort((a, b) => b.confidence - a.confidence);
+  }
+
+  private suggestNovelImprovements(mechanicalIdeas: Idea[]): Idea[] {
+    const ideas: Idea[] = [];
+    const hasCategories = new Set(mechanicalIdeas.map((i) => i.category));
+
+    if (!hasCategories.has("security")) {
+      ideas.push({
+        id: nextIdeaId(),
+        source: "improvement_pattern",
+        category: "security",
+        title: "Consider adding security threat modeling",
+        rationale: "No security-related ideas were identified. Projects without explicit security analysis often have blind spots in threat modeling.",
+        confidence: 0.55,
+        actions: ["add_security_pattern"],
+        tier: "backend-enriched",
+      });
+    }
+
+    if (!hasCategories.has("quality")) {
+      ideas.push({
+        id: nextIdeaId(),
+        source: "improvement_pattern",
+        category: "quality",
+        title: "Consider establishing quality baselines",
+        rationale: "No quality-related ideas were identified. Adding code quality baselines and review standards can prevent regressions.",
+        confidence: 0.50,
+        actions: ["add_test", "update_roadmap"],
+        tier: "backend-enriched",
+      });
+    }
+
+    if (!hasCategories.has("architecture")) {
+      ideas.push({
+        id: nextIdeaId(),
+        source: "improvement_pattern",
+        category: "architecture",
+        title: "Review architectural boundaries and dependencies",
+        rationale: "No architecture drift detected, but periodic boundary review is a best practice for healthy codebases.",
+        confidence: 0.45,
+        actions: ["update_architecture"],
+        tier: "backend-enriched",
+      });
+    }
+
+    return ideas;
+  }
+
+  generateChaosScenarios(): Idea[] {
+    resetIdeaCounter();
+    const ideas: Idea[] = [];
+    const config = this.getIdeationConfig();
+
+    if (!config.chaos.enabled) return ideas;
+
+    for (const scenario of config.chaos.scenarios) {
+      switch (scenario) {
+        case "backend_unavailable":
+          ideas.push({
+            id: nextIdeaId(),
+            source: "chaos_scenario",
+            category: "chaos",
+            title: "Resilience: Handle backend unavailability",
+            rationale: "What if the primary intelligence backend is unavailable? Add fallback paths and graceful degradation for all backend-dependent features.",
+            confidence: 0.7,
+            actions: ["add_requirement", "add_test"],
+            tier: "backend-enriched",
+          });
+          break;
+        case "requirement_change":
+          ideas.push({
+            id: nextIdeaId(),
+            source: "chaos_scenario",
+            category: "chaos",
+            title: "Resilience: Handle mid-implementation requirement changes",
+            rationale: "What if requirements change during implementation? Design for adaptability with clear interfaces and minimal coupling.",
+            confidence: 0.65,
+            actions: ["add_requirement"],
+            tier: "backend-enriched",
+          });
+          break;
+        case "test_coverage_drop":
+          ideas.push({
+            id: nextIdeaId(),
+            source: "chaos_scenario",
+            category: "chaos",
+            title: "Resilience: Prevent test coverage regression",
+            rationale: "What if test coverage drops below threshold? Add CI gates that enforce minimum coverage and alert on regression.",
+            confidence: 0.75,
+            actions: ["add_test", "update_roadmap"],
+            tier: "backend-enriched",
+          });
+          break;
+        default:
+          ideas.push({
+            id: nextIdeaId(),
+            source: "chaos_scenario",
+            category: "chaos",
+            title: `Resilience: Handle ${scenario} scenario`,
+            rationale: `Consider adding resilience measures for the "${scenario}" failure scenario.`,
+            confidence: 0.5,
+            actions: ["add_requirement"],
+            tier: "backend-enriched",
+          });
+      }
+    }
+
+    return ideas;
+  }
+
+  private getIdeationConfig(): IdeationConfig {
+    try {
+      const config = loadConfig(this.projectPath);
+      return (config as any).ideation || DEFAULT_IDEATION_CONFIG;
+    } catch {
+      return DEFAULT_IDEATION_CONFIG;
+    }
+  }
+
   formatIdeas(ideas: Idea[]): string {
     if (ideas.length === 0) return "No improvement ideas identified for this project.";