diff --git a/docs/superpowers/specs/2026-06-16-geo-agent-article-optimizer-design.md b/docs/superpowers/specs/2026-06-16-geo-agent-article-optimizer-design.md
index 3fe718c..9cf4c69 100644
--- a/docs/superpowers/specs/2026-06-16-geo-agent-article-optimizer-design.md
+++ b/docs/superpowers/specs/2026-06-16-geo-agent-article-optimizer-design.md
@@ -14,11 +14,16 @@ The MVP is a local web application:
 2. System extracts a candidate fact card.
 3. User confirms or edits the fact card.
 4. Confirmed fact card is saved as a reusable local brand template.
-5. System optimizes the article under fact-card constraints.
-6. System runs quality gates.
-7. Failed checks trigger targeted rewriting for up to two rounds.
-8. User previews optimized content and QA report.
-9. User downloads Markdown and a basic Word document.
+5. System generates three optimization candidates under fact-card constraints:
+   `标准GEO版`, `去AI味版`, and `综合增强版`.
+6. System runs quality gates for each candidate.
+7. Failed checks trigger targeted rewriting for up to two rounds inside each
+   candidate path.
+8. System scores each candidate for GEO quality and AI-flavor/style quality.
+9. User compares all candidates side by side, with `综合增强版` highlighted as
+   the recommended default.
+10. User downloads Markdown, Word, and QA artifacts for the selected candidate
+    or the full comparison.
 
 ## Explicitly Out Of Scope
 
@@ -36,12 +41,15 @@ The MVP is a local web application:
 flowchart TD
   A["Input Article"] --> B["Auto Analyze"]
   B --> C["Confirm Fact Card"]
-  C --> D["Optimize Article"]
-  D --> E["Quality Check"]
-  E -->|Pass| F["Preview Result"]
-  E -->|Fail| G["Targeted Rewrite"]
-  G --> D
-  F --> H["Download Markdown / Word"]
+  C --> D["Generate Three Candidates"]
+  D --> E1["标准GEO版 QA"]
+  D --> E2["去AI味版 QA"]
+  D --> E3["综合增强版 QA"]
+  E1 --> F["Compare Results"]
+  E2 --> F
+  E3 --> F
+  F --> G["Select Candidate"]
+  G --> H["Download Markdown / Word / QA"]
 ```
 
 ## Page Areas
@@ -78,17 +86,24 @@ Fields:
 
 The user must resolve uncertain items before optimization starts.
 
-### Optimized Result
+### Candidate Comparison
 
 Display:
 
+- Candidate label: `标准GEO版`, `去AI味版`, or `综合增强版`.
+- Method summary that explains what this candidate optimized for.
 - Optimized title.
 - Summary.
 - Optimized body.
-- Image suggestions.
+- QA status and failed/warned rule count.
+- GEO score.
+- AI-flavor/style score.
+- Timing.
 - Changed sections.
 
-The UI should mark content that needs user confirmation.
+The UI should mark content that needs user confirmation and should make
+`综合增强版` visually identifiable as the recommended default without hiding the
+other two candidates.
 
 ### Quality Report
 
@@ -98,9 +113,11 @@ Display each gate as pass, warn, or fail, with evidence, reason, suggested fix,
 
 Downloads:
 
-- `optimized.md`
-- `optimized.docx`
-- `qa_report.json`
+- Selected candidate: `optimized.md`, `optimized.docx`, `qa_report.json`.
+- Full comparison: `variant_comparison.json`.
+- If all candidate files are exported together, use stable Chinese labels in the
+  metadata and ASCII-safe file names on disk, such as
+  `standard-geo.md`, `anti-ai-flavor.md`, and `integrated-enhanced.md`.
 
 ## Internal Agent Nodes
 
@@ -110,11 +127,23 @@ The product is delivered as a simple web app, but the internals are split into e
 flowchart LR
   A["InputNormalizer"] --> B["FactExtractor"]
   B --> C["UserConfirmedFactCard"]
-  C --> D["ArticleOptimizer"]
-  D --> E["QualityInspector"]
-  E -->|fail| F["TargetedRewriter"]
-  F --> E
-  E -->|pass/warn| G["Exporter"]
+  C --> D["OptimizationVariantPlanner"]
+  D --> E1["标准GEO版 ArticleOptimizer"]
+  D --> E2["去AI味版 ArticleOptimizer"]
+  D --> E3["综合增强版 ArticleOptimizer"]
+  E1 --> F1["QualityInspector + StyleScorer"]
+  E2 --> F2["QualityInspector + StyleScorer"]
+  E3 --> F3["QualityInspector + StyleScorer"]
+  F1 -->|fail| G1["TargetedRewriter"]
+  F2 -->|fail| G2["TargetedRewriter"]
+  F3 -->|fail| G3["TargetedRewriter"]
+  G1 --> F1
+  G2 --> F2
+  G3 --> F3
+  F1 --> H["VariantComparator"]
+  F2 --> H
+  F3 --> H
+  H --> I["Exporter"]
 ```
 
 ### LLM Provider Integration
@@ -133,12 +162,14 @@ DEEPSEEK_THINKING=disabled
 
 Rules:
 
-- `src/lib/llm/client.ts` exposes `generateText`, `generateJson<T>`, `isLlmConfigured`, and `getLlmProviderStatus`.
+- `src/lib/llm/client.ts` exposes `generateText`, `generateJson<T>`,
+  `generateValidatedJson`, `isLlmConfigured`, and `getLlmProviderStatus`.
 - `LLM_PROVIDER` defaults to `deepseek` when unset.
 - DeepSeek is accessed through the OpenAI-compatible SDK with `baseURL` set to `https://api.deepseek.com`.
 - `generateJson<T>` must use JSON output mode and prompts that explicitly require valid JSON only.
 - Thinking mode is disabled by default for deterministic article rewrites and structured QA output.
-- Missing credentials use deterministic local fallbacks so the MVP remains testable and usable without a live API key.
+- Missing credentials and provider failures surface as explicit API errors; the
+  workflow must not silently fall back when the user expects live LLM behavior.
 - Provider errors are normalized inside the LLM client before they reach workflow nodes or API routes.
 
 ### InputNormalizer
@@ -212,6 +243,49 @@ Forbidden:
 - Change industry.
 - Add exaggerated marketing promises.
 
+### OptimizationVariantPlanner
+
+Purpose: create a fixed set of candidate methods for one confirmed fact card.
+
+The first comparison version always creates exactly three candidates:
+
+| Variant Key | Label | Method |
+| --- | --- | --- |
+| `standard_geo` | `标准GEO版` | Current GEO rewrite behavior: fact-card fidelity, platform fit, clear structure, and QA repair. |
+| `anti_ai_flavor` | `去AI味版` | GEO rewrite plus localized Stop Slop rules to remove AI-flavored prose patterns. |
+| `integrated_enhanced` | `综合增强版` | Balances GEO density, factual trust, platform fit, readability, and AI-flavor reduction. |
+
+Candidate generation may run sequentially in the first implementation to avoid
+provider rate-limit problems and to keep progress events understandable. The
+API response still returns the three candidates together for side-by-side
+comparison.
+
+### Stop Slop / AI-Flavor Rules
+
+The `hardikpandya/stop-slop` repository is an MIT-licensed writing skill rather
+than an installable runtime dependency. The original rules are mostly English
+writing rules, so the product should not copy them blindly into Chinese article
+optimization.
+
+The first implementation uses localized guidance derived from the rule intent:
+
+- Remove template openers and filler transitions, such as generic "本文将",
+  "值得注意的是", "从某种意义上", and repeated "通过...实现..." chains.
+- Replace empty business language with concrete claims already present in the
+  fact card.
+- Avoid formulaic contrast paragraphs that first list what something is not and
+  then reveal what it is.
+- Avoid slogan-like short fragments that sound like pull quotes instead of
+  article prose.
+- Prefer active, specific Chinese sentences with clear actors when the source
+  facts identify an actor.
+- Vary paragraph length and sentence rhythm without using theatrical emphasis.
+
+If substantial text from the upstream Stop Slop files is copied into this
+repository, add the MIT license notice to the committed artifact. A distilled
+Chinese rule set written for this product can live in source without vendoring
+the upstream repository.
+
 ### QualityInspector
 
 Purpose: convert the document's issue list into executable quality gates.
@@ -236,6 +310,53 @@ Examples:
 - Delete or mark unsupported claims for hallucination risk.
 - Warn instead of rewriting when image-text confidence is low.
 
+### StyleScorer
+
+Purpose: score each candidate for AI-flavor risk and naturalness without turning
+style concerns into hard QA failures.
+
+The first version returns a 0-50 score with five 0-10 dimensions:
+
+| Dimension | Question |
+| --- | --- |
+| `directness` | Does the article state concrete points instead of announcing them? |
+| `rhythm` | Do sentence and paragraph lengths vary naturally? |
+| `specificity` | Are claims concrete and tied to the fact card? |
+| `trust` | Does the prose avoid exaggerated intimacy, sweeping claims, and unsupported certainty? |
+| `density` | Can obvious filler be removed without losing meaning? |
+
+Scores below 35 should show a visible warning on the candidate card. They should
+not block export.
+
+### GeoScore
+
+Purpose: reuse the existing GEO article performance rubric to score each
+candidate for fact integrity, platform fit, search intent fit, answer density,
+trust signal quality, and readability.
+
+The score is computed from the candidate article plus its QA report. It is a
+comparison aid for the three candidates, not a publishing guarantee.
+
+### VariantComparator
+
+Purpose: assemble the candidate list for the API response and frontend.
+
+Each candidate result includes:
+
+- `variant_key`
+- `variant_label`
+- `method_summary`
+- `article`
+- `qa_report`
+- `geo_score`
+- `style_score`
+- `rewrite_rounds`
+- `timing`
+- `is_recommended`
+
+`integrated_enhanced` is recommended by default unless it has a hard QA failure
+and another candidate does not.
+
 ## Quality Gates
 
 | Rule ID | Issue Prevented | First Version Behavior |
@@ -276,15 +397,25 @@ Examples:
 
 The first version uses local SQLite plus an export folder.
 
+The first implementation can reuse the existing `optimized_articles` and
+`qa_reports` tables by saving each candidate as a normal article revision with
+variant metadata inside the JSON payload. The matching QA report is saved
+against that revision. A separate comparison-run table is out of scope until the
+product needs historical side-by-side comparison beyond the immediate job
+result.
+
 ```text
 data/
   app.db
   exports/
     job_xxx/
-      original.md
       optimized.md
       optimized.docx
       qa_report.json
+      variant_comparison.json
+      standard-geo.md
+      anti-ai-flavor.md
+      integrated-enhanced.md
 ```
 
 ### `brand_template`
@@ -358,6 +489,9 @@ One revision of optimized content.
 {
   "job_id": "job_xxx",
   "revision": 2,
+  "variant_key": "integrated_enhanced",
+  "variant_label": "综合增强版",
+  "method_summary": "同时优化GEO信息密度、事实可信度、平台适配和表达自然度。",
   "title": "Optimized title",
   "summary": "Optimized summary",
   "body_markdown": "Optimized body in Markdown",
@@ -367,7 +501,22 @@ One revision of optimized content.
       "suggestion": "Use product dashboard screenshot; avoid unrelated people photos"
     }
   ],
-  "changed_sections": ["title", "first paragraph"]
+  "changed_sections": ["title", "first paragraph"],
+  "geo_score": {
+    "total": 8.1,
+    "rationale": "事实一致性与答案密度较好，平台适配仍需复核。"
+  },
+  "style_score": {
+    "total": 42,
+    "dimensions": {
+      "directness": 8,
+      "rhythm": 8,
+      "specificity": 9,
+      "trust": 8,
+      "density": 9
+    },
+    "warnings": []
+  }
 }
 ```
 
@@ -408,9 +557,13 @@ Examples:
 
 ### QA Failure
 
-Hard failures block export. Warnings allow export with visible confirmation prompts.
+Hard failures do not block export in the current product direction. The app must
+preserve export files and show visible warnings so the user can review the
+candidate manually.
 
-Failed checks trigger targeted rewrite for up to two rounds. After two failed rounds, the app stops rewriting and shows manual review fields.
+Failed checks trigger targeted rewrite for up to two rounds inside each
+candidate. After two failed rounds, the app stops rewriting that candidate and
+shows manual review fields.
 
 ## Acceptance Criteria
 
@@ -420,9 +573,14 @@ The MVP is complete when:
 2. System can extract a fact card and require user confirmation.
 3. Confirmed fact card can be saved and reused as a local brand template.
 4. System can generate an optimized article without changing confirmed facts.
-5. System can generate a structured QA report for the 10 quality gates.
-6. Hard failures block export until fixed or manually reviewed.
-7. User can download Markdown and a basic Word document.
+5. System can generate exactly three labeled candidates: `标准GEO版`,
+   `去AI味版`, and `综合增强版`.
+6. System can generate a structured QA report for the 10 quality gates for each
+   candidate.
+7. System can score and compare the three candidates for AI-flavor/style quality.
+8. QA failures and low style scores remain visible but do not remove export links.
+9. User can download Markdown, a basic Word document, QA JSON, and a comparison
+   JSON artifact.
 
 ## Minimum Test Samples