refactor(automod): remove regex classifier — LLM is the sole judge

Delete fastClassifier.ts (manual regex patterns for phone/email/IP/crypto/
spam/toxicity) and simpleFallback.ts. These hardcoded patterns were the
source of false positives (Discord emoji snowflakes matched phone_number,
URL digits matched phone, etc.) and produced heuristic verdicts whenever
the LLM failed.

New flow: Message → LLM (with conversation context, media evidence, user
reputation) → verdict. On LLM failure the message is marked 'error' and
retried by the recovery worker — no heuristic verdicts, ever.

Discord markdown tokens (custom emoji/mentions/timestamps) are normalized
to readable placeholders ([emoji:name], @user, @role, #channel, [time])
before reaching the LLM via discordTokens.ts.

services/discord-gateway/src/modules/ai-moderation/ai-analysis-worker.ts

@@ -1,20 +1,15 @@
 /**
  * ai-analysis-worker.ts
  *
- * Two-pass AI moderation analysis worker (Piscina-compatible).
+ * AI moderation analysis worker (Piscina-compatible).
  *
  * ## Pipeline
  *
- *   Message → Layer 1 (fast classifier / heuristic)
- *              │
- *              ├─ clear match → final result (no LLM call)
- *              └─ ambiguous    → Layer 2 (LLM evaluator)
+ *   Message → LLM evaluator (with conversation context + media evidence)
  *
- * Layer 1 runs synchronously in-memory. Layer 2 calls the LLM API via
- * the existing moderation pipeline (moderationOrchestrator).
- *
- * This file replaces the old `aiAnalysisWorker.ts` (archived) with a
- * simpler, unified worker that combines both layers.
+ * Every message is judged by the LLM — there is no regex/heuristic
+ * pre-classification. A failed LLM call yields an explicit "error" status
+ * (never a heuristic verdict), and the recovery worker retries it later.
  */
 
 import { createChildLogger } from "@/shared/logger/index";
@@ -23,8 +18,6 @@ import { initializeDatabase } from "../../shared/database/drizzle.js";
 import { messageStore } from "../message-capture/messageStore.js";
 import type { MessageRecord } from "../message-capture/types.js";
 import { buildConversationContext } from "./conversationContext.js";
-import { classifyMessage } from "./fastClassifier.js";
-import type { Layer1Result } from "./fastClassifier.js";
 import { runModerationAnalysis } from "./moderationOrchestrator.js";
 
 const logger = createChildLogger("ai-analysis-worker");
@@ -89,11 +82,7 @@ export interface MessageBatch {
 // Worker job types (Piscina entry point)
 type WorkerJob =
   | { type: "batch"; conversationKey: string; messages: MessageRecord[] }
-  | {
-      type: "individual";
-      message: MessageRecord;
-      skipNormalAnalysis: boolean;
-    };
+  | { type: "individual"; message: MessageRecord; skipNormalAnalysis: boolean };
 
 type BatchOkResponse = {
   ok: true;
@@ -186,39 +175,21 @@ export default async function workerRouter(
 }
 
 // ---------------------------------------------------------------------------
-// Two-pass pipeline
+// Single-pass LLM pipeline
 // ---------------------------------------------------------------------------
 
 /**
- * Runs the two-pass pipeline on a single message:
- *   1. Layer 1 — fast heuristic classifier
- *   2. Layer 2 (if cascade) — LLM-based evaluator
+ * Runs the LLM moderation analysis on a single message.
  *
- * Returns the combined AnalysisResult.
+ * The LLM verdict IS the result — confidence, severity, flags and
+ * explanation all come from the model. On failure the message is marked
+ * "error" (explicit, retryable) instead of receiving a heuristic verdict.
  */
-async function runTwoPassPipeline(
+async function runLLMAnalysis(
   message: MessageRecord,
   contextText: string,
   attachments: Awaited<ReturnType<typeof messageStore.getAttachmentsForMessages>>,
 ): Promise<AnalysisResult> {
-  // ── Layer 1: Fast classifier ──────────────────────────────────────────
-  const layer1Result: Layer1Result = classifyMessage(message);
-
-  logger.debug(
-    {
-      messageId: message.id,
-      layer1Flags: layer1Result.flags,
-      cascade: layer1Result.cascadeToLayer2,
-    },
-    "Layer 1 classification complete",
-  );
-
-  if (!layer1Result.cascadeToLayer2) {
-    // Layer 1 result is final — no LLM call needed
-    return buildResultFromLayer1(message.id, layer1Result);
-  }
-
-  // ── Layer 2: LLM-based evaluation ─────────────────────────────────────
   try {
     const moderationResult = await runModerationAnalysis({
       targets: [message],
@@ -231,45 +202,44 @@ async function runTwoPassPipeline(
     }
 
     const llmResult = moderationResult.results[0] as unknown as AnalysisResult;
-    return mergeLayers(layer1Result, llmResult);
+    if (llmResult.status === "error") {
+      return llmResult;
+    }
+
+    return {
+      messageId: llmResult.messageId,
+      status: llmResult.status ?? "clean",
+      flags: llmResult.flags ?? [],
+      categories: llmResult.categories ?? [],
+      severity: llmResult.severity ?? "none",
+      confidence: normalizeConfidence(llmResult.confidence),
+      recommendedAction: llmResult.recommendedAction ?? "none",
+      toxicityScore: llmResult.toxicityScore ?? 0,
+      harmScore: llmResult.harmScore ?? 0,
+      jailbreakScore: llmResult.jailbreakScore ?? 0,
+      safetyScore: llmResult.safetyScore ?? 0,
+      explanation:
+        llmResult.explanation?.trim() ||
+        (llmResult.status === "clean"
+          ? "Tidak ada indikasi pelanggaran."
+          : "Pesan terindikasi melanggar kebijakan (analisis AI)."),
+    };
   } catch (error) {
     const errorMsg = error instanceof Error ? error.message : String(error);
     logger.warn(
       { messageId: message.id, error: errorMsg },
-      "Layer 2 (LLM) analysis failed — falling back to Layer 1 result",
+      "LLM analysis failed for message",
     );
-    // Fallback to Layer 1 with reduced confidence
-    const fallback = buildResultFromLayer1(message.id, layer1Result);
-    fallback.confidence = Math.min(fallback.confidence, 0.4);
-    return fallback;
+    return buildFallbackResult(message.id, errorMsg);
   }
 }
 
-// ---------------------------------------------------------------------------
-// Result builders
-// ---------------------------------------------------------------------------
-
-function buildResultFromLayer1(
-  messageId: string,
-  layer1: Layer1Result,
-): AnalysisResult {
-  const status = layer1.severity === "none" ? "clean" as const : "flagged" as const;
-  const recommendedAction = mapSeverityToAction(layer1.severity);
-
-  return {
-    messageId,
-    status,
-    flags: layer1.flags,
-    categories: layer1.flags,
-    severity: layer1.severity === "high" ? "high" as const : layer1.severity === "medium" ? "medium" as const : "low" as const,
-    confidence: layer1.confidence,
-    recommendedAction,
-    toxicityScore: layer1.toxicityScore,
-    harmScore: layer1.harmScore,
-    jailbreakScore: 0,
-    safetyScore: 0,
-    explanation: layer1.explanation,
-  };
+/** Clamp LLM-provided confidence to [0, 1]; default by status when missing. */
+function normalizeConfidence(raw: number | undefined | null): number {
+  if (typeof raw === "number" && Number.isFinite(raw)) {
+    return Math.min(Math.max(raw, 0), 1);
+  }
+  return 0.7;
 }
 
 function buildFallbackResult(
@@ -292,70 +262,6 @@ function buildFallbackResult(
   };
 }
 
-function mergeLayers(
-  layer1: Layer1Result,
-  llmResult: AnalysisResult,
-): AnalysisResult {
-  // Merge flags from both layers (deduplicate)
-  const flagSet = new Set<string>([...layer1.flags, ...(llmResult.flags || [])]);
-
-  // Take the max severity
-  const severityOrder = ["none", "low", "medium", "high", "critical"] as const;
-  const l1Idx = severityOrder.indexOf(layer1.severity);
-  const l2Idx = severityOrder.indexOf(
-    (llmResult.severity ?? "none") as (typeof severityOrder)[number],
-  );
-  const finalSeverity = severityOrder[Math.max(l1Idx, l2Idx)];
-
-  // Combined confidence: weighted average favoring LLM when available
-  const combinedConfidence =
-    0.3 * layer1.confidence + 0.7 * (llmResult.confidence ?? 0.5);
-
-  // Combine scores (take max per dimension)
-  const toxicityScore = Math.max(
-    layer1.toxicityScore,
-    llmResult.toxicityScore ?? 0,
-  );
-  const harmScore = Math.max(layer1.harmScore, llmResult.harmScore ?? 0);
-
-  return {
-    messageId: llmResult.messageId,
-    status: llmResult.status === "error" ? "error" as const : llmResult.status ?? "clean" as const,
-    flags: Array.from(flagSet),
-    categories: [
-      ...new Set([
-        ...layer1.flags,
-        ...(llmResult.categories ?? []),
-      ]),
-    ],
-    severity: finalSeverity,
-    confidence: Math.min(combinedConfidence, 1),
-    recommendedAction: llmResult.recommendedAction ?? mapSeverityToAction(finalSeverity),
-    toxicityScore,
-    harmScore,
-    jailbreakScore: llmResult.jailbreakScore ?? 0,
-    safetyScore: llmResult.safetyScore ?? 0,
-    explanation: llmResult.explanation ?? layer1.explanation,
-  };
-}
-
-function mapSeverityToAction(
-  severity: "none" | "low" | "medium" | "high" | "critical",
-): AnalysisResult["recommendedAction"] {
-  switch (severity) {
-    case "none":
-      return "none";
-    case "low":
-      return "monitor";
-    case "medium":
-      return "review";
-    case "high":
-      return "delete";
-    case "critical":
-      return "escalate";
-  }
-}
-
 // ---------------------------------------------------------------------------
 // Batch handler
 // ---------------------------------------------------------------------------
@@ -391,16 +297,16 @@ async function processBatch(job: {
   const attachments =
     await messageStore.getAttachmentsForMessages(allMessageIds);
 
-  // Run two-pass pipeline for each message
+  // Run LLM analysis for each message
   const analysisResults = await Promise.all(
     messages.map(async (msg) => {
       try {
-        return await runTwoPassPipeline(msg, contextText, attachments);
+        return await runLLMAnalysis(msg, contextText, attachments);
       } catch (error) {
         const errorMsg = error instanceof Error ? error.message : String(error);
         logger.error(
           { messageId: msg.id, error: errorMsg },
-          "Two-pass pipeline failed for message",
+          "LLM analysis failed for message",
         );
         return buildFallbackResult(msg.id, errorMsg);
       }
@@ -435,7 +341,7 @@ async function processBatch(job: {
       saved: allRows.length,
       conversationKey,
     },
-    "Two-pass batch analysis complete",
+    "LLM batch analysis complete",
   );
 
   return { ok: true, conversationKey, rows: allRows };
@@ -450,22 +356,11 @@ async function processIndividual(job: {
   message: MessageRecord;
   skipNormalAnalysis: boolean;
 }): Promise<IndividualOkResponse | IndividualErrorResponse> {
-  const { message, skipNormalAnalysis } = job;
+  const { message } = job;
 
-  if (skipNormalAnalysis) {
-    // Use Layer 1 only (fast)
-    const layer1Result = classifyMessage(message);
-
-    if (!layer1Result.cascadeToLayer2) {
-      // Layer 1 is sufficient
-      return {
-        ok: true,
-        results: [buildResultFromLayer1(message.id, layer1Result)],
-      };
-    }
-  }
-
-  // Full analysis (context + two-pass)
+  // Full analysis (context + LLM). `skipNormalAnalysis` is accepted for
+  // compatibility with the old two-pass protocol but always runs the LLM —
+  // there is no heuristic path anymore.
   const contextBefore = await messageStore.getConversationContextBefore({
     channelId: message.channel_id,
     threadId: message.thread_id,
@@ -487,14 +382,14 @@ async function processIndividual(job: {
   ]);
 
   try {
-    const result = await runTwoPassPipeline(message, contextText, attachments);
+    const result = await runLLMAnalysis(message, contextText, attachments);
     return { ok: true, results: [result] };
   } catch (error) {
     const errorMsg = error instanceof Error ? error.message : String(error);
     logger.error(
       { messageId: message.id, error: errorMsg },
-      "Individual two-pass analysis failed",
+      "Individual LLM analysis failed",
     );
     return { ok: true, results: [buildFallbackResult(message.id, errorMsg)] };
   }
-}
+}

services/discord-gateway/src/modules/ai-moderation/conversationContext.ts

@@ -2,6 +2,7 @@ import { createChildLogger } from "@/shared/logger/index";
 import { encoding_for_model as encodingForModel } from "tiktoken";
 import { formatMediaEvidenceForPrompt } from "../message-capture/messageMetadata.js";
 import type { MessageRecord } from "../message-capture/types.js";
+import { sanitizeDiscordTokens } from "./discordTokens.js";
 
 const logger = createChildLogger("conversationContext");
 
@@ -67,7 +68,9 @@ export function formatMessageForPrompt(
   msg: MessageRecord,
   label: "context" | "target",
 ): string {
-  const content = msg.edited_content ?? msg.content;
+  const content = sanitizeDiscordTokens(
+    msg.edited_content ?? msg.content,
+  );
   const timestamp = formatTimestamp(msg.created_at);
   const mediaEvidence = formatMediaEvidenceForPrompt(msg.metadata);
   const mediaSuffix = mediaEvidence ? ` ${mediaEvidence}` : "";

services/discord-gateway/src/modules/ai-moderation/discordTokens.ts

@@ -0,0 +1,41 @@
+/**
+ * discordTokens.ts
+ *
+ * Normalizes Discord markdown tokens (custom emoji, user/role/channel
+ * mentions, timestamps) into readable placeholders before content reaches
+ * the LLM. The numeric snowflake IDs inside these tokens are meaningless to
+ * an LLM and were the source of repeated false positives in the old
+ * regex-based Layer 1 classifier — so raw IDs are never presented.
+ */
+
+// <:name:id> | <a:name:id> | <@id> | <@!id> | <@&id> | <#id> | <t:id:style>
+const DISCORD_TOKEN_RE =
+  /<(?:a?:([^>]{1,32}):(\d{17,20})|@!?(\d{17,20})|@&(\d{17,20})|#(\d{17,20})|t:(\d{10,11})(?::([tTdDRfF]))?)>/g;
+
+/**
+ * Replaces Discord markdown tokens with readable placeholders.
+ *
+ * - `<:name:id>` / `<a:name:id>` → `[emoji:name]`
+ * - `<@123>` / `<@!123>`          → `@user`
+ * - `<@&123>`                     → `@role`
+ * - `<#123>`                      → `#channel`
+ * - `<t:123:R>`                   → `[time]`
+ *
+ * No numeric IDs survive, so digit-shaped patterns can never match them.
+ */
+export function sanitizeDiscordTokens(content: string): string {
+  if (!content.includes("<")) return content;
+  return content.replace(
+    DISCORD_TOKEN_RE,
+    (_full, emojiName, _emojiId, _userId, _roleId, _channelId, _time, _style) => {
+      if (emojiName) return `[emoji:${emojiName}]`;
+      // Capture groups tell us which alternative matched by position:
+      // 3=user, 4=role, 5=channel, 6=time
+      if (_userId !== undefined) return "@user";
+      if (_roleId !== undefined) return "@role";
+      if (_channelId !== undefined) return "#channel";
+      if (_time !== undefined) return "[time]";
+      return " ";
+    },
+  );
+}

services/discord-gateway/src/modules/ai-moderation/fastClassifier.ts

@@ -1,419 +0,0 @@
-/**
- * fastClassifier.ts
- *
- * Layer 1 — Synchronous heuristic classifier for the two-pass moderation pipeline.
- * Runs BEFORE any LLM call. Catches obvious spam, NSFW patterns, repeated characters,
- * and other low-hanging fruit with zero network cost.
- *
- * When a strong heuristic match is found, `cascadeToLayer2` is `false` and the
- * result is used as the final verdict. Otherwise the message proceeds to the LLM.
- */
-
-import type { MessageRecord } from "../message-capture/types.js";
-
-// ---------------------------------------------------------------------------
-// Types
-// ---------------------------------------------------------------------------
-
-export interface Layer1Result {
-  flags: string[];
-  severity: "none" | "low" | "medium" | "high";
-  toxicityScore: number;
-  harmScore: number;
-  cascadeToLayer2: boolean;
-  confidence: number;
-  explanation: string;
-}
-
-// ---------------------------------------------------------------------------
-// Pattern definitions
-// ---------------------------------------------------------------------------
-
-interface Pattern {
-  name: string;
-  test: (content: string, mentions: number) => boolean;
-  severity: "low" | "medium" | "high";
-  score: number; // contribution to toxicity/harm score
-  category: "toxicity" | "harm" | "spam" | "safety";
-}
-
-// ── Zalgo / zero-width detection ─────────────────────────────────────────
-
-const ZALGO_RE =
-  new RegExp(
-  '[̀-ͯ҃-҉ؐ-ًؚ-ٰٟۖ-ۜ۟-ۤۧ-۪ۨ-ܑۭܰ-݊ަ-ްँ-ः़ा-्॑-॔ॢ-ॣঁ-ঃ়া-ৄে-ৈো-্ৗৢ-ৣ৾ਁ-ਃ਼ਾ-ੂੇ-ੈੋ-੍ੑੰ-ੱੵઁ-ઃ઼ા-ૅે-ૉો-્ૢ-ૣૺ-૿ଁ-ଃ଼ା-ୄେ-ୈୋ-୍ୖ-ୗୢ-ୣஂா-ூெ-ைொ-்ௗఀ-ఃా-ౄె-ైొ-్ౕ-ౖౢ-ౣಁ-ಃ಼ಾ-ೄೆ-ೈೊ-್ೕ-ೖೢ-ೣഀ-ഃ഻-഼ാ-ൄെ-ൈൊ-്ൗൢ-ൣඁ-ඃ්ා-ුූෘ-ෟෲ-ෳัิ-ฺ็-๎ັິ-ູົ-ຼ່-ໍ༘-༹༙༵༷༾-༿ཱ-྄྆-྇ྍ-ྗྙ-ྼ࿆ါ-ှၖ-ၙၞ-ၠၢ-ၤၧ-ၭၱ-ၴႂ-ႍႏႚ-ႝ፝-፟ᜒ-᜔ᜲ-᜴ᝒ-ᝓᝲ-ᝳ឴-៓៝᠋-᠍ᢩᤠ-ᤫᤰ-᤻ᨗ-ᨛᩕ-ᩞ᩠-᩿᩼᪰-᪾ᬀ-ᬄ᬴-᭄᭫-᭳ᮀ-ᮁᮢ-ᮥᮨ-ᮩ᮫-ᮭ᯦-᯳ᰤ-᰷᳐-᳔᳒-᳨᳭ᳲ-᳴᳷-᳹᷀-᷿​-‏
-  -⃐-⃰⳯-⵿⳱ⷠ-〪ⷿ-゙〯-゚꙯-꙲ꙴ-꙽ꚞ-ꚟ꛰-꛱ꠂ꠆ꠋꠣ-ꠧ꠬ꢀ-ꢁꢴ-ꣅ꣠-꣱ꣿ-꤉ꤦ-꤭ꥇ-꥓ꥠ-ꥼꦀ-ꦃ꦳-꧀ꧥꨩ-ꨶꩃꩌꩍꩻ-ꩽꪰꪲ-ꪴꪷ-ꪸꪾ-꪿꫁ꫫ-ꫯꫵ-꫶ꯣ-ꯪ꯬꯭ﬞ︀-️︠-︯-]|­|͏|؜ᅟᅠ឴឵᠎ -   ⁠-⁤⁦-ㅤﾠ￰-￸\u{1e001}\u{1e020}-\u{1e07f}',
-);
-
-const ZERO_WIDTH_RE = /[​-‍⁠­؜]/;
-
-// ── URL / invite / phone / email / crypto patterns ─────────────────────
-
-const URL_RE = /https?:\/\/[^\s"]+/gi;
-const INVITE_RE = /(?:discord\.(?:gg|com\/invite)|dsc\.gg)\/[a-zA-Z0-9_-]+/gi;
-const INVITE_CODE_RE = /(?:^|\s)([a-zA-Z0-9_-]{6,12})(?:\s|$)/g;
-// Word-boundary phone match. `(?<!\d)` / `(?!\d)` stop the matcher from
-// grabbing a slice out of a longer digit run (e.g. Discord snowflake IDs).
-const PHONE_RE =
-  /(?<!\d)(?:\+?\d{1,3}[-.\s]?)?\(?\d{2,4}\)?[-.\s]?\d{3,4}[-.\s]?\d{3,4}(?!\d)/g;
-const EMAIL_RE = /[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}/gi;
-const CRYPTO_RE =
-  /(?:0x[a-fA-F0-9]{40}|bc1[a-z0-9]{39,59}|1[a-km-zA-HJ-NP-Z1-9]{25,34}|3[a-km-zA-HJ-NP-Z1-9]{25,34})/g;
-const IP_RE = /\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b/g;
-
-// ── Discord markdown token sanitization ────────────────────────────────
-// Custom emoji (<:name:id>, <a:name:id>), user/role/channel mentions and
-// timestamps embed long numeric snowflakes. If left in the text, digit-based
-// patterns (phone_number, personal_info, ip_address_sharing) false-positive
-// on them — e.g. <:mambotongue:1463255254220148939> "matched" phone_number.
-const DISCORD_TOKEN_RE =
-  /<(?:a?:[^>]{1,32}:\d{17,20}|@!?\d{17,20}|@&\d{17,20}|#\d{17,20}|t:\d{10,11}(?::[tTdDRfF])?)>/g;
-
-/** Replaces Discord markdown tokens with a space so they can't trip patterns. */
-export function sanitizeDiscordTokens(content: string): string {
-  return content.replace(DISCORD_TOKEN_RE, " ");
-}
-
-// ── Spam / low-quality patterns ─────────────────────────────────────────
-
-const REPEATED_CHAR_RE = /(.)\1{8,}/; // 9+ repeated chars
-const REPEATED_WORD_RE = /\b(\w{3,})\b\s*\b\1\b\s*\b\1\b/; // same word 3x
-const EXCESSIVE_CAPS_RE = /[A-Z]{6,}/;
-const EXCESSIVE_EMOJI_RE =
-  /[\u{1F300}-\u{1F9FF}\u{2600}-\u{26FF}\u{2700}-\u{27BF}]/gu;
-const BASE64_RE =
-  /^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$/;
-const PHISHING_RE =
-  /(?:free\s*(?:nitro|gift|prime|steam|vbucks?)|click\s*(?:here|this)\s*(?:to|for)\s*(?:claim|win|verify)|login\s*:\s*\w+\s*password\s*:\s*\w+)/gi;
-
-// ── Toxicity patterns ───────────────────────────────────────────────────
-
-const HARASSMENT_RE =
-  /\b(?:fuck|shit|asshole|bitch|dickhead|cunt|motherfucker|bastard|piss\s*off|screw\s*you|go\s*(?:to\s*)?hell|kys|kill\s*(?:yourself| urself))\b/i;
-const HATE_SPEECH_RE =
-  /\b(?:nazi|white\s*supremacy|heil|racial\s*purity|race\s*war)\b/i;
-
-// ── Harm patterns ───────────────────────────────────────────────────────
-
-const SELF_HARM_RE =
-  /\b(?:kill\s*(?:myself|me)|end\s*(?:my|the)\s*(?:life|own)|suicide|want\s*(?:to\s*)?die|cut\s*(?:myself|my\s*wrists)|harm\s*myself)\b/i;
-const VIOLENCE_RE =
-  /\b(?:shoot|stab|bomb|massacre|terrorist|behead|torture|murder)\b/i;
-
-// ── Safety patterns ─────────────────────────────────────────────────────
-
-const PERSONAL_INFO_RE =
-  /\b(?:\d{3}-\d{2}-\d{4}|(?:\d{3}\s?){2}\d{4})\b/; // SSN / IDs
-const SEXTORTION_RE =
-  /\b(?:nudes?\s*(?:pic|photo|video|send|trade)|cp\s*(?:content|link|loli|shotacon)|underage|minor\s*(?:girl|boy|content))\b/i;
-const GROOMING_RE =
-  /\b(?:how\s*old\s*are\s*you|are\s*you\s*(?:alone|home\s*alone)|dm\s*me\s*(?:baby|honey|sweetie|cutie)|send\s*(?:nudes|pics))\b/i;
-
-// ── Mass-mention patterns ───────────────────────────────────────────────
-
-const EVERYONE_MENTION = /@everyone/g;
-const HERE_MENTION = /@here/g;
-const ROLE_MENTION = /<@&(\d+)>/g;
-
-// ── Pattern registry (ordered roughly by specificity) ───────────────────
-
-const PATTERNS: Pattern[] = [
-  // ── High severity ─────────────────────────────────────────────────
-  {
-    name: "self_harm",
-    test: (c) => SELF_HARM_RE.test(c),
-    severity: "high",
-    score: 0.9,
-    category: "harm",
-  },
-  {
-    name: "violence_threat",
-    test: (c) => VIOLENCE_RE.test(c),
-    severity: "high",
-    score: 0.85,
-    category: "harm",
-  },
-  {
-    name: "sextortion",
-    test: (c) => SEXTORTION_RE.test(c),
-    severity: "high",
-    score: 0.95,
-    category: "safety",
-  },
-  {
-    name: "grooming",
-    test: (c) => GROOMING_RE.test(c),
-    severity: "high",
-    score: 0.9,
-    category: "safety",
-  },
-  {
-    name: "hate_speech",
-    test: (c) => HATE_SPEECH_RE.test(c),
-    severity: "high",
-    score: 0.85,
-    category: "toxicity",
-  },
-  {
-    name: "harassment",
-    test: (c) => HARASSMENT_RE.test(c),
-    severity: "medium",
-    score: 0.6,
-    category: "toxicity",
-  },
-  {
-    name: "phishing",
-    test: (c) => PHISHING_RE.test(c),
-    severity: "high",
-    score: 0.85,
-    category: "harm",
-  },
-  // ── Spam / low quality ────────────────────────────────────────────
-  {
-    name: "mass_everyone_mention",
-    test: (_c, mentions) => mentions >= 3,
-    severity: "medium",
-    score: 0.65,
-    category: "spam",
-  },
-  {
-    name: "excessive_caps",
-    test: (c) => {
-      const caps = (c.match(EXCESSIVE_CAPS_RE) || []).join("");
-      return caps.length > 0 && caps.length / Math.max(c.length, 1) > 0.5;
-    },
-    severity: "low",
-    score: 0.3,
-    category: "spam",
-  },
-  {
-    name: "repeated_characters",
-    test: (c) => REPEATED_CHAR_RE.test(c),
-    severity: "low",
-    score: 0.25,
-    category: "spam",
-  },
-  {
-    name: "repeated_words",
-    test: (c) => REPEATED_WORD_RE.test(c),
-    severity: "low",
-    score: 0.25,
-    category: "spam",
-  },
-  {
-    name: "zalgo_text",
-    test: (c) => ZALGO_RE.test(c) || ZERO_WIDTH_RE.test(c),
-    severity: "medium",
-    score: 0.6,
-    category: "spam",
-  },
-  {
-    name: "excessive_emojis",
-    test: (c) => {
-      const emojiCount = (c.match(EXCESSIVE_EMOJI_RE) || []).length;
-      const textLen = c.replace(EXCESSIVE_EMOJI_RE, "").trim().length;
-      return emojiCount >= 5 && textLen < emojiCount;
-    },
-    severity: "low",
-    score: 0.2,
-    category: "spam",
-  },
-  {
-    name: "base64_gibberish",
-    test: (c) => c.length >= 20 && BASE64_RE.test(c.trim()),
-    severity: "low",
-    score: 0.2,
-    category: "spam",
-  },
-  // ── Medium severity ───────────────────────────────────────────────
-  {
-    name: "personal_info",
-    test: (c) => PERSONAL_INFO_RE.test(c),
-    severity: "medium",
-    score: 0.6,
-    category: "safety",
-  },
-  {
-    name: "discord_invite",
-    test: (c) => INVITE_RE.test(c),
-    severity: "low",
-    score: 0.2,
-    category: "spam",
-  },
-  {
-    name: "url_only",
-    test: (c) => {
-      const urls = c.match(URL_RE);
-      if (!urls) return false;
-      const textWithoutUrls = c.replace(URL_RE, "").trim();
-      return urls.length >= 3 && textWithoutUrls.length === 0;
-    },
-    severity: "low",
-    score: 0.25,
-    category: "spam",
-  },
-  {
-    name: "phone_number",
-    test: (c) => PHONE_RE.test(c),
-    severity: "medium",
-    score: 0.5,
-    category: "safety",
-  },
-  {
-    name: "email_address",
-    test: (c) => EMAIL_RE.test(c),
-    severity: "low",
-    score: 0.3,
-    category: "safety",
-  },
-  {
-    name: "crypto_address",
-    test: (c) => CRYPTO_RE.test(c),
-    severity: "medium",
-    score: 0.5,
-    category: "spam",
-  },
-  {
-    name: "ip_address_sharing",
-    test: (c) => IP_RE.test(c),
-    severity: "low",
-    score: 0.3,
-    category: "safety",
-  },
-];
-
-// ---------------------------------------------------------------------------
-// Pattern matcher — count mentions
-// ---------------------------------------------------------------------------
-
-function countMentions(content: string): number {
-  let count = 0;
-  const everyoneMatches = content.match(EVERYONE_MENTION);
-  if (everyoneMatches) count += everyoneMatches.length;
-  const hereMatches = content.match(HERE_MENTION);
-  if (hereMatches) count += hereMatches.length;
-  const roleMatches = content.match(ROLE_MENTION);
-  if (roleMatches) count += roleMatches.length;
-  return count;
-}
-
-// ---------------------------------------------------------------------------
-// Main classifier
-// ---------------------------------------------------------------------------
-
-/**
- * Runs Layer 1 heuristic classification on a message.
- * Returns a `Layer1Result` with matched flags and a decision on
- * whether to cascade to Layer 2 (LLM).
- */
-export function classifyMessage(message: MessageRecord): Layer1Result {
-  const content = message.edited_content ?? message.content;
-  if (!content || content.trim().length === 0) {
-    return {
-      flags: [],
-      severity: "none",
-      toxicityScore: 0,
-      harmScore: 0,
-      cascadeToLayer2: true, // empty content still needs metadata check
-      confidence: 0,
-      explanation: "No text content to classify",
-    };
-  }
-
-  const mentions = countMentions(content);
-  // Strip Discord markdown tokens (emoji/mention snowflakes) before pattern
-  // matching so digit-based patterns don't false-positive on them.
-  const sanitized = sanitizeDiscordTokens(content);
-  const matchedFlags: string[] = [];
-  const severityWeights: Record<string, number> = {
-    low: 1,
-    medium: 2,
-    high: 3,
-  };
-
-  let maxSeverityWeight = 0;
-  let totalToxicityScore = 0;
-  let totalHarmScore = 0;
-  let totalSafetyScore = 0;
-  let totalSpamScore = 0;
-  const matchedPatternDetails: string[] = [];
-
-  for (const pattern of PATTERNS) {
-    if (pattern.test(sanitized, mentions)) {
-      matchedFlags.push(pattern.name);
-      matchedPatternDetails.push(pattern.name);
-
-      const weight = severityWeights[pattern.severity] || 1;
-      maxSeverityWeight = Math.max(maxSeverityWeight, weight);
-
-      switch (pattern.category) {
-        case "toxicity":
-          totalToxicityScore += pattern.score;
-          break;
-        case "harm":
-          totalHarmScore += pattern.score;
-          break;
-        case "safety":
-          totalSafetyScore += pattern.score;
-          break;
-        case "spam":
-          totalSpamScore += pattern.score;
-          break;
-      }
-    }
-  }
-
-  // ── Determine final severity ───────────────────────────────────────
-
-  let finalSeverity: "none" | "low" | "medium" | "high" = "none";
-  if (maxSeverityWeight >= 3) finalSeverity = "high";
-  else if (maxSeverityWeight >= 2) finalSeverity = "medium";
-  else if (maxSeverityWeight >= 1) finalSeverity = "low";
-
-  // ── Determine if we should cascade ─────────────────────────────────
-  // Cascade to Layer 2 whenever:
-  //   1. No high-severity match was found, OR
-  //   2. Only spam/low-quality patterns matched (need LLM for nuance)
-  // Do NOT cascade when a clear high-severity harm/safety/toxicity match
-  // was found — the heuristic is sufficient.
-
-  const hasHighSeverityPattern = matchedFlags.some((f) => {
-    const p = PATTERNS.find((p) => p.name === f);
-    return p && p.severity === "high";
-  });
-  const hasOnlyLowSeveritySpam = matchedFlags.every((f) => {
-    const p = PATTERNS.find((p) => p.name === f);
-    return p && p.category === "spam" && p.severity !== "high";
-  });
-
-  // Cascade if no matches, only spam, or low/medium severity toxicity/safety
-  const cascadeToLayer2 =
-    matchedFlags.length === 0 ||
-    hasOnlyLowSeveritySpam ||
-    (finalSeverity !== "high" && hasHighSeverityPattern === false);
-
-  // ── Compute final scores (clamped 0-1) ─────────────────────────────
-
-  const toxicityScore = Math.min(totalToxicityScore, 1);
-  const harmScore = Math.min(totalHarmScore, 1);
-
-  // ── Confidence ─────────────────────────────────────────────────────
-
-  const confidence = cascadeToLayer2
-    ? 0.4 + 0.1 * matchedFlags.length // low confidence when punting to LLM
-    : 0.6 + 0.4 * (1 - matchedFlags.length / PATTERNS.length);
-
-  const explanation =
-    matchedFlags.length > 0
-      ? `Layer 1 matched: ${matchedPatternDetails.join(", ")}`
-      : "No heuristic patterns matched";
-
-  return {
-    flags: matchedFlags,
-    severity: finalSeverity,
-    toxicityScore,
-    harmScore,
-    cascadeToLayer2,
-    confidence: Math.min(confidence, 0.99),
-    explanation,
-  };
-}

services/discord-gateway/src/modules/ai-moderation/index.ts

@@ -1,9 +1,12 @@
 export { startPendingAIAnalysisWorker } from "./aiAnalyzer.js";
 export { runModerationAnalysis } from "./moderationOrchestrator.js";
 export { buildSystemPrompt } from "./moderationPrompt.js";
-export { runSimpleTextFallback } from "./simpleFallback.js";
+export { sanitizeDiscordTokens } from "./discordTokens.js";
 
-// ── New two-pass pipeline exports ──────────────────────────────────────────
-export { classifyMessage } from "./fastClassifier.js";
-export type { Layer1Result } from "./fastClassifier.js";
-export type { AnalysisInput, AnalysisResult, WorkerConfig, MessageBatch } from "./ai-analysis-worker.js";
+// ── Single-pass LLM pipeline exports ─────────────────────────────────────
+export type {
+  AnalysisInput,
+  AnalysisResult,
+  WorkerConfig,
+  MessageBatch,
+} from "./ai-analysis-worker.js";

services/discord-gateway/src/modules/ai-moderation/individualFallbackProcessor.ts

@@ -82,7 +82,6 @@ async function processIndividualFallback(
       | { ok: false; results: AnalysisResult[]; error: string };
 
     let analysisResult: { results: AnalysisResult[] } | null = null;
-    let usedSimpleFallback = false;
 
     if (workerResult.ok) {
       const stillIncomplete = workerResult.results.some((r) =>
@@ -96,38 +95,12 @@ async function processIndividualFallback(
       }
     }
 
-    // Step 2: If normal analysis failed, try SIMPLE fallback via worker
-    if (!analysisResult) {
-      logger.info(
-        { messageId },
-        "Normal analysis failed -- trying simple text fallback via worker",
-      );
-
-      const simpleResult = (await workerPool.run({
-        type: "individual",
-        message,
-        skipNormalAnalysis: true,
-      } as unknown)) as
-        | { ok: true; results: AnalysisResult[] }
-        | { ok: false; results: AnalysisResult[]; error: string };
-
-      if (simpleResult.ok) {
-        analysisResult = simpleResult;
-        usedSimpleFallback = true;
-        exhaustedOnIncomplete = false;
-      }
-    }
-
+    // No heuristic fallback: an incomplete/errored LLM result stays a
+    // retryable error — the recovery worker picks it up later. Producing a
+    // regex/wordlist verdict here would reintroduce false positives.
     if (!analysisResult) {
       throw new Error(
-        `Both normal and simple analysis failed for message ${messageId}`,
-      );
-    }
-
-    if (usedSimpleFallback) {
-      logger.info(
-        { messageId, status: analysisResult.results[0]?.status },
-        "Used simple text fallback for individual message (via worker)",
+        `LLM analysis failed for message ${messageId}`,
       );
     }
 

services/discord-gateway/src/modules/ai-moderation/moderationBuilders.ts

@@ -7,6 +7,7 @@
 
 import { messageStore } from "../message-capture/messageStore.js";
 import type { MessageRecord } from "../message-capture/types.js";
+import { sanitizeDiscordTokens } from "./discordTokens.js";
 
 /** Simple XML-escaping for content text. */
 export function escapeXml(s: string): string {
@@ -29,7 +30,7 @@ export function getAnalysisContent(message: MessageRecord): string {
     /\[(?:Attachment|Sticker):[^\]]*\]|\[Embed\]/g,
     "",
   );
-  return stripped.trim();
+  return sanitizeDiscordTokens(stripped).trim();
 }
 
 /**

services/discord-gateway/src/modules/ai-moderation/simpleFallback.ts

@@ -1,182 +0,0 @@
-/**
- * simpleFallback.ts
- *
- * Simple two-step text fallback for cheap/small models.
- * Step 1: Single-word classification (clean/warn/flagged).
- * Step 2: Real analysis text (only if not clean).
- * Extracted from moderationOrchestrator.ts.
- */
-import { createChildLogger } from "@/shared/logger/index";
-import type {
-  AnalysisResult,
-  MessageRecord,
-} from "../message-capture/types.js";
-import { llmChat } from "./llmClient.js";
-import { getAnalysisContent } from "./moderationBuilders.js";
-import { sanitizeAiContent } from "./moderationPrompt.js";
-import { getUserProfile } from "./userProfileStore.js";
-
-const log = createChildLogger("simpleFallback");
-
-// ---------------------------------------------------------------------------
-// Simple text-only fallback
-// ---------------------------------------------------------------------------
-
-/**
- * Simple two-step text fallback for cheap/small models.
- * Step 1: Single-word classification (clean/warn/flagged).
- * Step 2: Real analysis text (only if not clean).
- */
-export async function runSimpleTextFallback(
-  message: MessageRecord,
-): Promise<AnalysisResult> {
-  const content = getAnalysisContent(message);
-  const MAX_CONTENT_CHARS = 500;
-  const truncatedContent =
-    content.length > MAX_CONTENT_CHARS
-      ? `${content.slice(0, MAX_CONTENT_CHARS)}...`
-      : content;
-
-  let userProfileCtx = "";
-  try {
-    const profile = await getUserProfile(message.user_id);
-    if (profile?.profile_summary) {
-      userProfileCtx = `\n\nProfil pengirim pesan:\n${sanitizeAiContent(profile.profile_summary, 3000, false)}\n`;
-    }
-  } catch {
-    /* non-fatal */
-  }
-
-  // Step 1: Single-word classification
-  const classifyPrompt = `Pesan berikut perlu diklasifikasikan sebagai: clean, warn, atau flagged.
-
-Aturan:
-- clean: pesan biasa, percakapan normal, tidak ada pelanggaran
-- warn: spam ringan, promosi tidak jelas, atau pelanggaran ringan
-- flagged: harassment, SARA, NSFW, judi, ancaman, atau pelanggaran serius
-
-PENTING (False Positive Prevention):
-- Slang Indonesia ("anjay", "wkwk", "njir", "gws", dll) dan makian umum ("asu", "anjing", "bangsat") yang TIDAK ditujukan ke orang lain = clean.
-- Konten coding/programming (kode, log error, SQL, command line, error message, stack trace, nama library) = clean. JANGAN flag hanya karena ada kata "error" atau "crash" dalam konteks teknis.
-- Nama proyek, tools, framework (IMPHNEN, Bete, Cursor, Claude, React, Discord) = clean.
-- Percakapan multilingual (campuran Indonesia-Inggris) = clean.
-${userProfileCtx}
-Pesan: "${truncatedContent}"
-
-Jawab HANYA dengan satu kata: clean, warn, atau flagged`;
-
-  let status: "clean" | "warn" | "flagged";
-  try {
-    const completion = await llmChat({
-      messages: [{ role: "user", content: classifyPrompt }],
-      max_tokens: 10,
-      temperature: 0.1,
-    });
-    const raw =
-      completion?.choices[0]?.message?.content?.trim().toLowerCase() ?? "";
-    if (raw.includes("flagged")) status = "flagged";
-    else if (raw.includes("warn")) status = "warn";
-    else status = "clean";
-    log.info({ messageId: message.id, status, raw }, "Simple fallback step 1");
-  } catch (error) {
-    log.warn(
-      {
-        messageId: message.id,
-        error: error instanceof Error ? error.message : String(error),
-      },
-      "Simple fallback step 1 failed — defaulting to clean",
-    );
-    status = "clean";
-  }
-
-  // Step 2: Reason + category (only if not clean)
-  let analysis: string;
-  let category = "";
-
-  if (status === "clean") {
-    analysis = `${message.username ?? "user"}: ${content.length > 200 ? `${content.slice(0, 200)}...` : content}. Percakapan normal, tidak ada pelanggaran.`;
-  } else {
-    category = status === "flagged" ? "harassment" : "spam";
-    const categoryOptions =
-      status === "flagged" ? "harassment, gambling, atau sara" : "spam";
-    const reasonPrompt = `Pesan berikut telah diklasifikasikan sebagai "${status}".
-${userProfileCtx}
-Pesan: "${truncatedContent}"
-
-Jelaskan dalam 1-2 kalimat Bahasa Indonesia: APA yang melanggar dan KENAPA. Jangan gunakan kata "mungkin" atau "sepertinya". Jangan tulis ulang pesan. Langsung ke alasan.
-
-Setelah alasan, sebutkan Kategori: ${categoryOptions}
-
-Contoh untuk "flagged":
-Mengandung kata kasar terarah ke individu tertentu sebagai hinaan.
-Kategori: harassment
-
-Contoh untuk "flagged":
-Promosi situs judi online dengan link dan ajakan.
-Kategori: gambling
-
-Contoh untuk "warn":
-Promosi channel Discord tanpa konteks, berpotensi spam.
-Kategori: spam
-
-Contoh untuk "warn":
-Bahasa kasar ringan yang tidak terarah.
-Kategori: spam`;
-
-    try {
-      const completion = await llmChat({
-        messages: [{ role: "user", content: reasonPrompt }],
-        max_tokens: 80,
-        temperature: 0.3,
-      });
-      analysis = completion?.choices[0]?.message?.content?.trim() ?? "";
-      if (!analysis || analysis.length < 5) {
-        analysis = `Pesan diklasifikasikan sebagai ${status} oleh sistem moderasi otomatis.`;
-      }
-      const categoryMatch = analysis.match(/[Kk]ategori:\s*(\w+)/i);
-      if (categoryMatch) {
-        const parsedCat = categoryMatch[1].toLowerCase();
-        if (["harassment", "spam", "gambling", "sara"].includes(parsedCat))
-          category = parsedCat;
-        analysis = analysis.replace(/[Kk]ategori:\s*\w+\s*/i, "").trim();
-      }
-      log.info(
-        {
-          messageId: message.id,
-          status,
-          category,
-          analysis: analysis.slice(0, 100),
-        },
-        "Simple fallback step 2",
-      );
-    } catch (error) {
-      analysis = `Pesan diklasifikasikan sebagai ${status} oleh sistem moderasi otomatis berdasarkan analisis konten.`;
-      log.warn(
-        {
-          messageId: message.id,
-          error: error instanceof Error ? error.message : String(error),
-        },
-        "Simple fallback step 2 failed",
-      );
-    }
-  }
-
-  return {
-    messageId: message.id,
-    status,
-    flags: status === "clean" ? [] : [category],
-    score: status === "flagged" ? 0.7 : status === "warn" ? 0.4 : 0,
-    analysis,
-    categories: status === "clean" ? [] : [category],
-    severity:
-      status === "flagged" ? "medium" : status === "warn" ? "low" : "none",
-    confidence: 0.6,
-    recommendedAction:
-      status === "flagged" ? "review" : status === "warn" ? "warn" : "none",
-    policyVersion: "default-simple-2026-06",
-    evidence:
-      status !== "clean"
-        ? [content.length > 120 ? `${content.slice(0, 120)}...` : content]
-        : [],
-  };
-}