feat(moderation): make moderation more lenient and add timeout fallback behavior

The moderation system now uses a "pass/review" strategy instead of "pass/review/block", treating hard violations the same as review (only routing to manual review rather than auto-rejecting). Add fallback-approve behavior in the hook system so slow moderation APIs never silently block normal content when they time out or get cancelled - timed-out moderation now approves with "ReviewedBy: system" instead of leaving the zero-value result that would reject content. Update post/comment/vote services and handlers to use the new unified behavior. Simplify moderation prompts to emphasize "宁可放过，不可误伤" (prefer false positives over false negatives).

internal/handler/post_handler.go

@@ -108,11 +108,6 @@ func (h *PostHandler) Create(c *gin.Context) {
 
 		post, err := h.postService.Create(c.Request.Context(), userID, req.Title, content, segments, req.Images, req.ChannelID, req.ClientRequestID)
 	if err != nil {
-		var moderationErr *service.PostModerationRejectedError
-		if errors.As(err, &moderationErr) {
-			response.BadRequest(c, moderationErr.UserMessage())
-			return
-		}
 		// 幂等命中"进行中"占位：提示客户端稍候，避免重复提交
 		if errors.Is(err, service.ErrDuplicatePostRequest) {
 			response.ErrorWithStatusCode(c, http.StatusTooManyRequests, 429, err.Error())

internal/handler/vote_handler.go

@@ -42,11 +42,6 @@ func (h *VoteHandler) CreateVotePost(c *gin.Context) {
 
 	post, err := h.voteService.CreateVotePost(c.Request.Context(), userID, &req)
 	if err != nil {
-		var moderationErr *service.PostModerationRejectedError
-		if errors.As(err, &moderationErr) {
-			response.BadRequest(c, moderationErr.UserMessage())
-			return
-		}
 		// 幂等命中"进行中"占位：提示客户端稍候，避免重复提交
 		if errors.Is(err, service.ErrDuplicatePostRequest) {
 			response.ErrorWithStatusCode(c, http.StatusTooManyRequests, 429, err.Error())

internal/pkg/hook/hook.go

@@ -215,6 +215,7 @@ func (m *Manager) TriggerWithMetadata(ctx context.Context, hookType HookType, us
 
 	var asyncHooks []*hookEntry
 
+	var firstSyncErr error
 	for _, entry := range entries {
 		if !entry.hook.Enabled {
 			continue
@@ -226,6 +227,9 @@ func (m *Manager) TriggerWithMetadata(ctx context.Context, hookType HookType, us
 		}
 
 		if err := m.executeHook(entry, hookCtx); err != nil {
+			if firstSyncErr == nil {
+				firstSyncErr = err
+			}
 			zap.L().Error("Hook execution failed",
 				zap.String("name", entry.hook.Name),
 				zap.String("type", string(hookType)),
@@ -256,12 +260,29 @@ func (m *Manager) TriggerWithMetadata(ctx context.Context, hookType HookType, us
 		}()
 	}
 
-	return nil
+	return firstSyncErr
 }
 
 func (m *Manager) executeHook(entry *hookEntry, ctx *HookContext) error {
 	start := time.Now()
 
+	// Derive a cancellable context bounded by the hook's Timeout so that
+	// long-running hook work (e.g. HTTP calls to the moderation API) is
+	// actually cancelled when the timeout fires, instead of leaking and
+	// racing on shared metadata after executeHook returns.
+	if entry.hook.Timeout > 0 {
+		hookCtx, cancel := context.WithTimeout(ctx.Ctx, entry.hook.Timeout)
+		defer cancel()
+
+		ctx = &HookContext{
+			Ctx:      hookCtx,
+			HookType: ctx.HookType,
+			UserID:   ctx.UserID,
+			Data:     ctx.Data,
+			Metadata: ctx.Metadata,
+		}
+	}
+
 	var err error
 	if entry.hook.Timeout > 0 {
 		done := make(chan error, 1)
@@ -280,13 +301,17 @@ func (m *Manager) executeHook(entry *hookEntry, ctx *HookContext) error {
 
 		select {
 		case err = <-done:
-		case <-time.After(entry.hook.Timeout):
+		case <-ctx.Ctx.Done():
-			err = context.DeadlineExceeded
+			err = ctx.Ctx.Err()
 			zap.L().Warn("Hook timeout",
 				zap.String("name", entry.hook.Name),
 				zap.Duration("timeout", entry.hook.Timeout),
+				zap.Error(err),
 			)
 		}
+		// Wait for the spawned goroutine to observe cancellation and return,
+		// so it cannot keep writing to ctx.Metadata after executeHook returns.
+		<-done
 	} else {
 		err = entry.hook.Func(ctx)
 	}

internal/pkg/hook/moderation_hooks.go

@@ -2,6 +2,7 @@
 
 import (
 	"context"
+	"errors"
 	"strings"
 	"time"
 
@@ -382,40 +383,69 @@ func (m *ModerationHooks) RegisterAll(manager *Manager) {
 
 func (m *ModerationHooks) ModeratePost(ctx context.Context, manager *Manager, data *PostModerateHookData) *ModerationResult {
 	result := &ModerationResult{}
-	manager.TriggerWithMetadata(ctx, HookPostPreModerate, data.AuthorID, data, map[string]any{
+	if err := manager.TriggerWithMetadata(ctx, HookPostPreModerate, data.AuthorID, data, map[string]any{
 		"result": result,
-	})
+	}); err != nil {
+		applyModerationFallback(result, err)
+	}
 	return result
 }
 
 func (m *ModerationHooks) ModerateComment(ctx context.Context, manager *Manager, data *CommentModerateHookData) *ModerationResult {
 	result := &ModerationResult{}
-	manager.TriggerWithMetadata(ctx, HookCommentPreModerate, data.AuthorID, data, map[string]any{
+	if err := manager.TriggerWithMetadata(ctx, HookCommentPreModerate, data.AuthorID, data, map[string]any{
 		"result": result,
-	})
+	}); err != nil {
+		applyModerationFallback(result, err)
+	}
 	return result
 }
 
 func (m *ModerationHooks) ModerateAvatar(ctx context.Context, manager *Manager, data *UserAvatarModerateHookData) *ModerationResult {
 	result := &ModerationResult{}
-	manager.TriggerWithMetadata(ctx, HookUserAvatarPreModerate, 0, data, map[string]any{
+	if err := manager.TriggerWithMetadata(ctx, HookUserAvatarPreModerate, 0, data, map[string]any{
 		"result": result,
-	})
+	}); err != nil {
+		applyModerationFallback(result, err)
+	}
 	return result
 }
 
 func (m *ModerationHooks) ModerateCover(ctx context.Context, manager *Manager, data *UserCoverModerateHookData) *ModerationResult {
 	result := &ModerationResult{}
-	manager.TriggerWithMetadata(ctx, HookUserCoverPreModerate, 0, data, map[string]any{
+	if err := manager.TriggerWithMetadata(ctx, HookUserCoverPreModerate, 0, data, map[string]any{
 		"result": result,
-	})
+	}); err != nil {
+		applyModerationFallback(result, err)
+	}
 	return result
 }
 
 func (m *ModerationHooks) ModerateBio(ctx context.Context, manager *Manager, data *UserBioModerateHookData) *ModerationResult {
 	result := &ModerationResult{}
-	manager.TriggerWithMetadata(ctx, HookUserBioPreModerate, 0, data, map[string]any{
+	if err := manager.TriggerWithMetadata(ctx, HookUserBioPreModerate, 0, data, map[string]any{
 		"result": result,
-	})
+	}); err != nil {
+		applyModerationFallback(result, err)
+	}
 	return result
 }
+
+// applyModerationFallback handles moderation hook timeouts/cancellations by
+// falling back to "approved by system" instead of leaving the zero-value
+// result (Approved=false) which would silently reject otherwise-fine content.
+func applyModerationFallback(result *ModerationResult, err error) {
+	if err == nil {
+		return
+	}
+	if errors.Is(err, context.DeadlineExceeded) || errors.Is(err, context.Canceled) {
+		result.Approved = true
+		result.ReviewedBy = "system"
+		result.RejectReason = ""
+		result.NeedsReview = false
+		result.Error = err
+		zap.L().Warn("Moderation hook timed out or was cancelled, fallback approve",
+			zap.Error(err),
+		)
+	}
+}

internal/pkg/openai/client.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"image"
 	_ "image/gif"
@@ -21,55 +22,41 @@ import (
 	xdraw "golang.org/x/image/draw"
 )
 
-const moderationSystemPrompt = `你是中文社区的内容审核助手，负责对"帖子标题、正文、配图"做联合审核。目标是平衡社区安全与正常交流：必须拦截高风险违规内容，但不要误伤正常玩梗、二创、吐槽和轻度调侃。请只输出指定JSON。
+const moderationSystemPrompt = `你是中文社区的内容审核助手，负责对"帖子标题、正文、配图"做联合审核。原则是**宁可放过，不可误伤**：只有明确违法违规内容才标记 review 交人工复核，其余一律 pass。请只输出指定JSON。
 
-审核流程：
+核心原则：
-1) 先判断是否命中硬性违规；
+- 除明确违法违规外，不要拦截或送审正常内容，包括尖锐吐槽、玩梗、二创、争论；
-2) 再判断语境（玩笑/自嘲/朋友间互动/作品讨论）；
+- 判定从严，倾向放行：宁可放过十个可疑，不可误伤一个正常。
-3) 做文图交叉判断（文本+图片合并理解）；
-4) 给出 result 与简短 reason。
 
-硬性违规（命中任一项必须 result=block）：
+只有命中**明确违法违规**时才输出 result=review：
-A. 宣传对立与煽动撕裂：
+A. 违法犯罪：明确宣传违法犯罪行为、教唆或指导他人犯罪（如毒品、枪支、诈骗教程）。
-- 明确煽动群体对立、地域对立、性别对立、民族宗教对立，鼓动仇恨、排斥、报复。
+B. 真实暴力威胁：针对具体个人或群体的实质性暴力威胁、人身伤害恐吓。
-B. 严重人身攻击与网暴引导：
+C. 色情低俗：明确色情、露骨性描写或诱导性内容；正常人体艺术、二次创作用感形象不在此列。
-- 持续性侮辱贬损、羞辱人格、号召围攻/骚扰/挂人/线下冲突。
+D. 诈骗引流：明确的诈骗信息、钓鱼链接、黑产引流。
-C. 开盒/人肉/隐私暴露：
+E. 未成年保护：涉及未成年人的色情或剥削内容。
-- 故意公开、拼接、索取他人可识别隐私信息（姓名+联系方式、身份证号、住址、学校单位、车牌、定位轨迹等）；
+F. 开盒/人肉：故意公开他人可识别隐私信息（身份证号、住址、联系方式、定位轨迹）并伴有曝光意图。
-- 图片/截图中出现可识别隐私信息并伴随曝光意图，也按违规处理。
+G. 极端仇恨：鼓动对特定族裔/宗教/残障群体的仇恨与暴力，含纳粹等极端符号。
-D. 其他高危违规：
-- 违法犯罪、暴力威胁、极端仇恨、色情低俗、诈骗引流、恶意广告等。
 
-可疑内容（需要人工复审，result=review）：
+以下情形即使存在也**一律 pass**（不送审、不拦截）：
-- 内容含义模糊，无法确定是否存在违规意图；
-- 涉及敏感话题但未明确违规（如政治人物、社会热点事件等）；
-- 存在轻微争议性表达，但不完全符合硬性违规标准；
-- AI无法准确判断的文化/地域特定表达。
-
-放行规则（以下通常 result=pass）：
 - 正常玩梗、表情包、谐音梗、二次创作、无恶意的吐槽；
-- 非定向、轻度口语化吐槽（无明确攻击对象、无网暴号召、无隐私暴露）；
+- 非定向、轻度口语化吐槽、玩笑、自嘲、朋友间互动；
-- 对社会事件/作品的理性讨论、观点争论（即使语气尖锐，但未煽动对立或人身攻击）。
+- 对社会事件/作品的理性讨论、观点争论（即使语气尖锐、用词激烈）；
-
+- 一般性粗口、调侃、讽刺，未煽动对立或人身攻击的；
-边界判定：
+- 对政治人物/社会热点的评论、争议性观点表达；
-- 若只是"梗文化表达"且不指向现实伤害，优先通过；
+- 含义模糊但无明显违法意图的内容。
-- 若存在明确伤害意图（煽动、围攻、曝光隐私），必须拒绝；
-- 对模糊内容不因个别粗口直接拒绝，需结合对象、意图、号召性和可执行性综合判断；
-- 如果实在无法确定是否违规，标记为 review 状态交由人工复审。
 
 reason 要求：
-- result=block 时：中文10-30字，说明核心违规点；
+- result=review 时：中文10-30字，说明疑似违法点；
-- result=review 时：中文10-30字，说明可疑原因；
 - result=pass 时：reason 为空字符串。
 
 输出格式（严格）：
 仅输出一行JSON对象，不要Markdown，不要额外解释：
-{"result": "pass"/"review"/"block", "reason": "..."}`
+{"result": "pass"/"review", "reason": "..."}`
 
 const (
 	defaultMaxImagesPerModerationRequest = 1
+	maxAllowedImagesPerModerationRequest = 4
 	maxModerationResultRetries           = 3
-	maxChatCompletionRetries             = 3
 	initialRetryBackoff                  = 500 * time.Millisecond
 	maxDownloadImageBytes                = 10 * 1024 * 1024
 	maxModerationImageSide               = 1280
@@ -165,53 +152,61 @@ func (c *clientImpl) ModerateComment(ctx context.Context, content string, images
 	return c.moderateContentInBatches(ctx, prompt.String(), images)
 }
 
-const imageModerationSystemPrompt = `你是图片内容审核助手，负责审核用户头像和背景图片。目标是确保图片内容符合社区规范。请只输出指定JSON。
+const imageModerationSystemPrompt = `你是图片内容审核助手，负责审核用户头像和背景图片。原则是**宁可放过，不可误伤**：只有明确违法违规的图片才标记 review 交人工复核，其余一律 pass。请只输出指定JSON。
 
-硬性违规（命中任一项必须 result=block）：
+核心原则：
-- 色情低俗、裸露、性暗示内容
+- 除明确违法违规外，不要拦截或送审正常图片；
-- 暴力血腥、恐怖画面
+- 判定从严，倾向放行：宁可放过十张可疑，不可误伤一张正常。
-- 违法犯罪相关内容
-- 明确的政治敏感宣传
-- 恶意广告、诈骗信息
-- 仇恨歧视符号或标志
 
-可疑内容（result=review）：
+只有命中**明确违法违规**时才输出 result=review：
-- 图片含义模糊，无法确定是否存在违规
+- 色情低俗：明确色情、露骨性描写或诱导性图片；正常人体艺术、二次创作用感形象不在此列；
-- 轻微争议性内容但不完全违规
+- 真实暴力/血腥：明确展示严重暴力、凶杀、虐待等违法犯罪画面；
-- AI无法准确判断的内容
+- 违法犯罪相关：明确涉及毒品、枪支、诈骗、黑产等内容；
+- 未成年保护：涉及未成年人的色情或剥削图片；
+- 诈骗引流：明确的诈骗二维码、钓鱼链接、黑产广告；
+- 极端仇恨：纳粹等极端仇恨符号或标志。
 
-放行规则（result=pass）：
+以下图片即使存在也**一律 pass**（不送审、不拦截）：
-- 正常风景、人物、动物、动漫等图片
+- 正常风景、人物、动物、动漫等图片；
-- 表情包、梗图
+- 表情包、梗图、二次创作；
-- 正常的艺术创作、摄影作品
+- 正常的艺术创作、摄影作品；
+- 含义模糊但无明显违法意图的图片。
+
+reason 要求：
+- result=review 时：中文10-30字，说明疑似违法点；
+- result=pass 时：reason 为空字符串。
 
 输出格式（严格）：
 仅输出一行JSON对象，不要Markdown，不要额外解释：
-{"result": "pass"/"review"/"block", "reason": "..."}`
+{"result": "pass"/"review", "reason": "..."}`
 
-const bioModerationSystemPrompt = `你是用户个性签名内容审核助手，负责审核用户个人简介/签名。目标是平衡社区安全与正常自我表达。请只输出指定JSON。
+const bioModerationSystemPrompt = `你是用户个性签名内容审核助手，负责审核用户个人简介/签名。原则是**宁可放过，不可误伤**：只有明确违法违规内容才标记 review 交人工复核，其余一律 pass。请只输出指定JSON。
 
-硬性违规（命中任一项必须 result=block）：
+核心原则：
-- 明确的违法犯罪、暴力威胁内容
+- 除明确违法违规外，不要拦截或送审正常签名；
-- 色情低俗、性暗示描述
+- 判定从严，倾向放行：宁可放过十个可疑，不可误伤一个正常。
-- 诈骗引流、恶意广告
-- 明确煽动群体对立、仇恨
-- 恶意公开他人隐私信息
 
-可疑内容（result=review）：
+只有命中**明确违法违规**时才输出 result=review：
-- 内容含义模糊，无法确定违规意图
+- 明确违法犯罪、暴力威胁内容；
-- 涉及敏感话题但未明确违规
+- 色情低俗、露骨性暗示描述；
-- AI无法准确判断的表达
+- 诈骗引流、黑产广告；
+- 恶意公开他人可识别隐私信息；
+- 涉及未成年人的色情或剥削内容。
 
-放行规则（result=pass）：
+以下签名即使存在也**一律 pass**（不送审、不拦截）：
-- 正常的自我介绍、心情表达
+- 正常的自我介绍、心情表达；
-- 玩梗、幽默、吐槽
+- 玩梗、幽默、吐槽、谐音梗；
-- 引用、歌词、诗句等
+- 引用、歌词、诗句等；
-- 理性的观点表达
+- 理性的观点表达、对社会事件的评论；
+- 含义模糊但无明显违法意图的内容。
+
+reason 要求：
+- result=review 时：中文10-30字，说明疑似违法点；
+- result=pass 时：reason 为空字符串。
 
 输出格式（严格）：
 仅输出一行JSON对象，不要Markdown，不要额外解释：
-{"result": "pass"/"review"/"block", "reason": "..."}`
+{"result": "pass"/"review", "reason": "..."}`
 
 func (c *clientImpl) ModerateImage(ctx context.Context, imageURL string) (*ModerationResponse, error) {
 	if !c.IsEnabled() {
@@ -226,42 +221,11 @@ func (c *clientImpl) ModerateImage(ctx context.Context, imageURL string) (*Moder
 	cleanImages := normalizeImageURLs([]string{imageURL})
 	optimizedImages := c.optimizeImagesForModeration(ctx, cleanImages)
 
-	var lastErr error
+	resp, err := c.moderateWithRetry(ctx, imageModerationSystemPrompt, userPrompt, optimizedImages)
-	for attempt := 0; attempt < maxModerationResultRetries; attempt++ {
-		replyText, err := c.chatCompletion(ctx, c.cfg.ModerationModel, imageModerationSystemPrompt, userPrompt, optimizedImages, 0.1, 220)
 	if err != nil {
-			lastErr = err
+		return nil, fmt.Errorf("image moderation failed after %d attempts: %w", maxModerationResultRetries, err)
-		} else {
-			parsed := struct {
-				Result string `json:"result"`
-				Reason string `json:"reason"`
-			}{}
-			if err := json.Unmarshal([]byte(extractJSONObject(replyText)), &parsed); err != nil {
-				lastErr = fmt.Errorf("failed to parse moderation result: %w", err)
-			} else {
-				result := ModerationResultPass
-				switch parsed.Result {
-				case "review":
-					result = ModerationResultReview
-				case "block":
-					result = ModerationResultBlock
 	}
-				return &ModerationResponse{
+	return resp, nil
-					Result: result,
-					Reason: parsed.Reason,
-				}, nil
-			}
-		}
-
-		if attempt == maxModerationResultRetries-1 {
-			break
-		}
-		if sleepErr := sleepWithBackoff(ctx, attempt); sleepErr != nil {
-			return nil, sleepErr
-		}
-	}
-
-	return nil, fmt.Errorf("image moderation failed after %d attempts: %w", maxModerationResultRetries, lastErr)
 }
 
 func (c *clientImpl) ModerateBio(ctx context.Context, bio string) (*ModerationResponse, error) {
@@ -278,42 +242,11 @@ func (c *clientImpl) ModerateBio(ctx context.Context, bio string) (*ModerationRe
 }
 
 func (c *clientImpl) moderateWithCustomPrompt(ctx context.Context, systemPrompt string, userPrompt string) (*ModerationResponse, error) {
-	var lastErr error
+	resp, err := c.moderateWithRetry(ctx, systemPrompt, userPrompt, nil)
-	for attempt := 0; attempt < maxModerationResultRetries; attempt++ {
-		replyText, err := c.chatCompletion(ctx, c.cfg.ModerationModel, systemPrompt, userPrompt, nil, 0.1, 220)
 	if err != nil {
-			lastErr = err
+		return nil, fmt.Errorf("moderation failed after %d attempts: %w", maxModerationResultRetries, err)
-		} else {
-			parsed := struct {
-				Result string `json:"result"`
-				Reason string `json:"reason"`
-			}{}
-			if err := json.Unmarshal([]byte(extractJSONObject(replyText)), &parsed); err != nil {
-				lastErr = fmt.Errorf("failed to parse moderation result: %w", err)
-			} else {
-				result := ModerationResultPass
-				switch parsed.Result {
-				case "review":
-					result = ModerationResultReview
-				case "block":
-					result = ModerationResultBlock
 	}
-				return &ModerationResponse{
+	return resp, nil
-					Result: result,
-					Reason: parsed.Reason,
-				}, nil
-			}
-		}
-
-		if attempt == maxModerationResultRetries-1 {
-			break
-		}
-		if sleepErr := sleepWithBackoff(ctx, attempt); sleepErr != nil {
-			return nil, sleepErr
-		}
-	}
-
-	return nil, fmt.Errorf("moderation failed after %d attempts: %w", maxModerationResultRetries, lastErr)
 }
 
 func (c *clientImpl) moderateContentInBatches(ctx context.Context, contentPrompt string, images []string) (*ModerationResponse, error) {
@@ -365,49 +298,18 @@ func (c *clientImpl) moderateSingleBatch(
 		totalBatches,
 	)
 
-	var lastErr error
+	resp, err := c.moderateWithRetry(ctx, moderationSystemPrompt, userPrompt, images)
-	for attempt := 0; attempt < maxModerationResultRetries; attempt++ {
-		replyText, err := c.chatCompletion(ctx, c.cfg.ModerationModel, moderationSystemPrompt, userPrompt, images, 0.1, 220)
 	if err != nil {
-			lastErr = err
-		} else {
-			parsed := struct {
-				Result string `json:"result"`
-				Reason string `json:"reason"`
-			}{}
-			if err := json.Unmarshal([]byte(extractJSONObject(replyText)), &parsed); err != nil {
-				lastErr = fmt.Errorf("failed to parse moderation result: %w", err)
-			} else {
-				result := ModerationResultPass
-				switch parsed.Result {
-				case "review":
-					result = ModerationResultReview
-				case "block":
-					result = ModerationResultBlock
-				}
-				return &ModerationResponse{
-					Result: result,
-					Reason: parsed.Reason,
-				}, nil
-			}
-		}
-
-		if attempt == maxModerationResultRetries-1 {
-			break
-		}
-		if sleepErr := sleepWithBackoff(ctx, attempt); sleepErr != nil {
-			return nil, sleepErr
-		}
-	}
-
 		return nil, fmt.Errorf(
 			"moderation batch %d/%d failed after %d attempts: %w",
 			batchNo,
 			totalBatches,
 			maxModerationResultRetries,
-		lastErr,
+			err,
 		)
 	}
+	return resp, nil
+}
 
 type chatCompletionsRequest struct {
 	Model          string                `json:"model"`
@@ -497,36 +399,69 @@ func (c *clientImpl) chatCompletion(
 		endpoint = baseURL + "/chat/completions"
 	}
 
-	var lastErr error
-	for attempt := 0; attempt < maxChatCompletionRetries; attempt++ {
 	body, statusCode, err := c.doChatCompletionRequest(ctx, endpoint, data)
 	if err != nil {
-			lastErr = err
+		return "", &chatCompletionError{StatusCode: 0, Err: err}
-		} else if statusCode >= 400 {
-			lastErr = fmt.Errorf("openai error status=%d body=%s", statusCode, string(body))
-			if !isRetryableStatusCode(statusCode) {
-				return "", lastErr
 	}
-		} else {
+	if statusCode >= 400 {
+		return "", &chatCompletionError{
+			StatusCode: statusCode,
+			Err:        fmt.Errorf("openai error status=%d body=%s", statusCode, string(body)),
+		}
+	}
+
 	var parsed chatCompletionsResponse
 	if err := json.Unmarshal(body, &parsed); err != nil {
-				return "", fmt.Errorf("decode response: %w", err)
+		return "", &chatCompletionError{
+			StatusCode: statusCode,
+			Err:        fmt.Errorf("decode response: %w", err),
+		}
 	}
 	if len(parsed.Choices) == 0 {
-				return "", fmt.Errorf("empty response choices")
+		return "", &chatCompletionError{
+			StatusCode: statusCode,
+			Err:        fmt.Errorf("empty response choices"),
+		}
 	}
 	return parsed.Choices[0].Message.Content, nil
 }
 
-		if attempt == maxChatCompletionRetries-1 {
+// chatCompletionError wraps errors from chatCompletion so callers can decide
-			break
+// retryability based on the upstream HTTP status code. StatusCode == 0 means
-		}
+// the request never reached the server (transport failure).
-		if sleepErr := sleepWithBackoff(ctx, attempt); sleepErr != nil {
+type chatCompletionError struct {
-			return "", sleepErr
+	StatusCode int
-		}
+	Err        error
 }
 
-	return "", lastErr
+func (e *chatCompletionError) Error() string {
+	if e.Err == nil {
+		return "chat completion error"
+	}
+	return e.Err.Error()
+}
+
+func (e *chatCompletionError) Unwrap() error {
+	return e.Err
+}
+
+// isRetryableModerationErr reports whether a moderation caller should retry
+// after the given chatCompletion error. Context cancellation and non-429 4xx
+// responses are not retryable; transport, 429, 5xx, and parsing errors are.
+func isRetryableModerationErr(err error) bool {
+	if err == nil {
+		return false
+	}
+	if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
+		return false
+	}
+	var ce *chatCompletionError
+	if errors.As(err, &ce) {
+		if ce.StatusCode >= 400 && ce.StatusCode != http.StatusTooManyRequests && ce.StatusCode < 500 {
+			return false
+		}
+	}
+	return true
 }
 
 func (c *clientImpl) doChatCompletionRequest(ctx context.Context, endpoint string, data []byte) ([]byte, int, error) {
@@ -550,13 +485,6 @@ func (c *clientImpl) doChatCompletionRequest(ctx context.Context, endpoint strin
 	return body, resp.StatusCode, nil
 }
 
-func isRetryableStatusCode(statusCode int) bool {
-	if statusCode == http.StatusTooManyRequests {
-		return true
-	}
-	return statusCode >= 500 && statusCode <= 599
-}
-
 func sleepWithBackoff(ctx context.Context, attempt int) error {
 	delay := initialRetryBackoff * time.Duration(1<<attempt)
 	timer := time.NewTimer(delay)
@@ -570,6 +498,63 @@ func sleepWithBackoff(ctx context.Context, attempt int) error {
 	}
 }
 
+// moderateWithRetry runs a single moderation request up to maxModerationResultRetries
+// times, retrying only on retryable chatCompletion errors. The underlying chatCompletion
+// no longer retries on its own, so the total number of upstream calls is bounded by
+// maxModerationResultRetries (previously 3x3=9).
+func (c *clientImpl) moderateWithRetry(
+	ctx context.Context,
+	systemPrompt, userPrompt string,
+	images []string,
+) (*ModerationResponse, error) {
+	var lastErr error
+	for attempt := 0; attempt < maxModerationResultRetries; attempt++ {
+		replyText, err := c.chatCompletion(ctx, c.cfg.ModerationModel, systemPrompt, userPrompt, images, 0.1, 220)
+		if err != nil {
+			lastErr = err
+		} else {
+			resp, parseErr := parseModerationReply(replyText)
+			if parseErr != nil {
+				lastErr = parseErr
+			} else {
+				return resp, nil
+			}
+		}
+
+		if attempt == maxModerationResultRetries-1 {
+			break
+		}
+		if !isRetryableModerationErr(lastErr) {
+			break
+		}
+		if sleepErr := sleepWithBackoff(ctx, attempt); sleepErr != nil {
+			return nil, sleepErr
+		}
+	}
+	return nil, lastErr
+}
+
+func parseModerationReply(replyText string) (*ModerationResponse, error) {
+	parsed := struct {
+		Result string `json:"result"`
+		Reason string `json:"reason"`
+	}{}
+	if err := json.Unmarshal([]byte(extractJSONObject(replyText)), &parsed); err != nil {
+		return nil, fmt.Errorf("failed to parse moderation result: %w", err)
+	}
+	result := ModerationResultPass
+	switch parsed.Result {
+	case "review":
+		result = ModerationResultReview
+	case "block":
+		result = ModerationResultBlock
+	}
+	return &ModerationResponse{
+		Result: result,
+		Reason: parsed.Reason,
+	}, nil
+}
+
 func normalizeImageURLs(images []string) []string {
 	clean := make([]string, 0, len(images))
 	for _, image := range images {
@@ -593,13 +578,14 @@ func extractJSONObject(raw string) string {
 }
 
 func (c *clientImpl) maxImagesPerModerationRequest() int {
-	if c.cfg.ModerationMaxImagesPerRequest <= 0 {
+	configured := c.cfg.ModerationMaxImagesPerRequest
+	if configured <= 0 {
 		return defaultMaxImagesPerModerationRequest
 	}
-	if c.cfg.ModerationMaxImagesPerRequest > 1 {
+	if configured > maxAllowedImagesPerModerationRequest {
-		return 1
+		return maxAllowedImagesPerModerationRequest
 	}
-	return c.cfg.ModerationMaxImagesPerRequest
+	return configured
 }
 
 func (c *clientImpl) optimizeImagesForModeration(ctx context.Context, images []string) []string {

internal/service/comment_service.go

@@ -2,6 +2,7 @@ package service
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"strings"
@@ -170,7 +171,7 @@ func (s *commentService) reviewCommentAsync(
 	fmt.Sscanf(userID, "%d", &authorID)
 
 	result := &hook.ModerationResult{}
-	s.hookManager.TriggerWithMetadata(context.Background(), hook.HookCommentPreModerate, authorID, &hook.CommentModerateHookData{
+	triggerErr := s.hookManager.TriggerWithMetadata(context.Background(), hook.HookCommentPreModerate, authorID, &hook.CommentModerateHookData{
 		CommentID: commentID,
 		PostID:    postID,
 		Content:   content,
@@ -181,6 +182,19 @@ func (s *commentService) reviewCommentAsync(
 		"result": result,
 	})
 
+	// Fallback-approve when a moderation hook times out or is cancelled, so a
+	// slow moderation API never silently rejects an otherwise-fine comment.
+	if triggerErr != nil && (errors.Is(triggerErr, context.DeadlineExceeded) || errors.Is(triggerErr, context.Canceled)) {
+		zap.L().Warn("Comment moderation hook timed out or was cancelled, fallback approve",
+			zap.String("comment_id", commentID),
+			zap.Error(triggerErr),
+		)
+		result.Approved = true
+		result.ReviewedBy = "system"
+		result.RejectReason = ""
+		result.NeedsReview = false
+	}
+
 	s.hookManager.Trigger(context.Background(), hook.HookCommentModerated, authorID, &hook.CommentModeratedHookData{
 		CommentID:    commentID,
 		PostID:       postID,

internal/service/post_ai_service.go

@@ -223,15 +223,13 @@ func (s *postAIService) ModeratePost(ctx context.Context, title, content string,
 				zap.Error(err),
 			)
 			return s.moderateTextWithTencent(ctx, title+" "+content,
-				func(reason string) error { return &PostModerationRejectedError{Reason: reason} },
 				func(reason string) error { return &PostModerationReviewError{Reason: reason} },
 			)
 		}
 
+		// block 与 review 同等处理：均仅送人工复审。
 		switch resp.Result {
-		case openai.ModerationResultBlock:
+		case openai.ModerationResultBlock, openai.ModerationResultReview:
-			return &PostModerationRejectedError{Reason: resp.Reason}
-		case openai.ModerationResultReview:
 			return &PostModerationReviewError{Reason: resp.Reason}
 		default:
 			return nil
@@ -239,7 +237,6 @@ func (s *postAIService) ModeratePost(ctx context.Context, title, content string,
 	}
 
 	return s.moderateTextWithTencent(ctx, title+" "+content,
-		func(reason string) error { return &PostModerationRejectedError{Reason: reason} },
 		func(reason string) error { return &PostModerationReviewError{Reason: reason} },
 	)
 }
@@ -256,15 +253,13 @@ func (s *postAIService) ModerateComment(ctx context.Context, content string, ima
 				zap.Error(err),
 			)
 			return s.moderateTextWithTencent(ctx, content,
-				func(reason string) error { return &CommentModerationRejectedError{Reason: reason} },
 				func(reason string) error { return &CommentModerationReviewError{Reason: reason} },
 			)
 		}
 
+		// block 与 review 同等处理：均仅送人工复审。
 		switch resp.Result {
-		case openai.ModerationResultBlock:
+		case openai.ModerationResultBlock, openai.ModerationResultReview:
-			return &CommentModerationRejectedError{Reason: resp.Reason}
-		case openai.ModerationResultReview:
 			return &CommentModerationReviewError{Reason: resp.Reason}
 		default:
 			return nil
@@ -272,7 +267,6 @@ func (s *postAIService) ModerateComment(ctx context.Context, content string, ima
 	}
 
 	return s.moderateTextWithTencent(ctx, content,
-		func(reason string) error { return &CommentModerationRejectedError{Reason: reason} },
 		func(reason string) error { return &CommentModerationReviewError{Reason: reason} },
 	)
 }
@@ -293,10 +287,9 @@ func (s *postAIService) ModerateImage(ctx context.Context, imageURL string) erro
 		return nil
 	}
 
+	// block 与 review 同等处理：均仅送人工复审。
 	switch resp.Result {
-	case openai.ModerationResultBlock:
+	case openai.ModerationResultBlock, openai.ModerationResultReview:
-		return &ImageModerationRejectedError{Reason: resp.Reason}
-	case openai.ModerationResultReview:
 		return &ImageModerationReviewError{Reason: resp.Reason}
 	default:
 		return nil
@@ -315,15 +308,13 @@ func (s *postAIService) ModerateBio(ctx context.Context, bio string) error {
 				zap.Error(err),
 			)
 			return s.moderateTextWithTencent(ctx, bio,
-				func(reason string) error { return &BioModerationRejectedError{Reason: reason} },
 				func(reason string) error { return &BioModerationReviewError{Reason: reason} },
 			)
 		}
 
+		// block 与 review 同等处理：均仅送人工复审。
 		switch resp.Result {
-		case openai.ModerationResultBlock:
+		case openai.ModerationResultBlock, openai.ModerationResultReview:
-			return &BioModerationRejectedError{Reason: resp.Reason}
-		case openai.ModerationResultReview:
 			return &BioModerationReviewError{Reason: resp.Reason}
 		default:
 			return nil
@@ -331,7 +322,6 @@ func (s *postAIService) ModerateBio(ctx context.Context, bio string) error {
 	}
 
 	return s.moderateTextWithTencent(ctx, bio,
-		func(reason string) error { return &BioModerationRejectedError{Reason: reason} },
 		func(reason string) error { return &BioModerationReviewError{Reason: reason} },
 	)
 }
@@ -339,7 +329,6 @@ func (s *postAIService) ModerateBio(ctx context.Context, bio string) error {
 func (s *postAIService) moderateTextWithTencent(
 	ctx context.Context,
 	text string,
-	rejectFactory func(string) error,
 	reviewFactory func(string) error,
 ) error {
 	if !s.isTencentEnabled() {
@@ -366,10 +355,9 @@ func (s *postAIService) moderateTextWithTencent(
 		reason = resp.Label + ": " + strings.Join(resp.Keywords, ", ")
 	}
 
+	// 腾讯云 block 也仅送审，与 AI 同语义。
 	switch resp.Suggestion {
-	case tencent.SuggestionBlock:
+	case tencent.SuggestionBlock, tencent.SuggestionReview:
-		return rejectFactory(reason)
-	case tencent.SuggestionReview:
 		return reviewFactory(reason)
 	default:
 		return nil

internal/service/post_service.go

@@ -2,6 +2,7 @@ package service
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"strconv"
@@ -216,7 +217,7 @@ func (s *postServiceImpl) reviewPostAsync(postID, userID, title, content string,
 	fmt.Sscanf(userID, "%d", &authorID)
 
 	result := &hook.ModerationResult{}
-	s.hookManager.TriggerWithMetadata(context.Background(), hook.HookPostPreModerate, authorID, &hook.PostModerateHookData{
+	triggerErr := s.hookManager.TriggerWithMetadata(context.Background(), hook.HookPostPreModerate, authorID, &hook.PostModerateHookData{
 		PostID:   postID,
 		Title:    title,
 		Content:  content,
@@ -226,6 +227,19 @@ func (s *postServiceImpl) reviewPostAsync(postID, userID, title, content string,
 		"result": result,
 	})
 
+	// Trigger can return context.DeadlineExceeded/Canceled if a moderation hook
+	// times out. In that case the result may not have been written at all
+	// (result.Approved stays false). Treat an unfinished moderation as
+	// "approved + system" rather than silently rejecting the post, so a slow
+	// moderation API never blocks normal content.
+	if triggerErr != nil && (errors.Is(triggerErr, context.DeadlineExceeded) || errors.Is(triggerErr, context.Canceled)) {
+		log.Printf("[WARN] Post moderation hook timed out or was cancelled, fallback approve post=%s err=%v", postID, triggerErr)
+		result.Approved = true
+		result.ReviewedBy = "system"
+		result.RejectReason = ""
+		result.NeedsReview = false
+	}
+
 	s.hookManager.Trigger(context.Background(), hook.HookPostModerated, authorID, &hook.PostModeratedHookData{
 		PostID:       postID,
 		AuthorID:     authorID,

internal/service/vote_service.go

@@ -177,7 +177,7 @@ func (s *voteService) reviewVotePostAsync(postID, userID, title, content string,
 	}
 
 	result := &hook.ModerationResult{}
-	s.hookManager.TriggerWithMetadata(context.Background(), hook.HookPostPreModerate, authorID, &hook.PostModerateHookData{
+	triggerErr := s.hookManager.TriggerWithMetadata(context.Background(), hook.HookPostPreModerate, authorID, &hook.PostModerateHookData{
 		PostID:   postID,
 		Title:    title,
 		Content:  content,
@@ -187,6 +187,16 @@ func (s *voteService) reviewVotePostAsync(postID, userID, title, content string,
 		"result": result,
 	})
 
+	// Fallback-approve when a moderation hook times out or is cancelled, so a
+	// slow moderation API never silently rejects an otherwise-fine vote post.
+	if triggerErr != nil && (errors.Is(triggerErr, context.DeadlineExceeded) || errors.Is(triggerErr, context.Canceled)) {
+		log.Printf("[WARN] Vote post moderation hook timed out or was cancelled, fallback approve post=%s err=%v", postID, triggerErr)
+		result.Approved = true
+		result.ReviewedBy = "system"
+		result.RejectReason = ""
+		result.NeedsReview = false
+	}
+
 	s.hookManager.Trigger(context.Background(), hook.HookPostModerated, authorID, &hook.PostModeratedHookData{
 		PostID:       postID,
 		AuthorID:     authorID,