@@ -42,6 +42,7 @@ interface OpenCodeMemConfig {
   autoCaptureMaxIterations?: number;
   autoCaptureIterationTimeout?: number;
   autoCaptureMaxRetries?: number;
+  autoCaptureMaxContextBytes?: number;
   autoCaptureLanguage?: string;
   memoryProvider?: "openai-chat" | "openai-responses" | "anthropic" | "minimax";
   memoryModel?: string;
@@ -81,6 +82,8 @@ interface OpenCodeMemConfig {
   userProfileCentroidDriftThreshold?: number;
   userProfileEmbeddingMinDescriptionLength?: number;
   userProfileMinEvidenceForRetention?: number;
+  userProfileAutoCleanupEnabled?: boolean;
+  userProfileAutoCleanupInterval?: number;
   userProfileValidationEnabled?: boolean;
   showAutoCaptureToasts?: boolean;
   showUserProfileToasts?: boolean;
@@ -152,6 +155,7 @@ const DEFAULTS: Required<
   autoCaptureMaxIterations: 5,
   autoCaptureIterationTimeout: 30000,
   autoCaptureMaxRetries: 3,
+  autoCaptureMaxContextBytes: 131072,
   aiSessionRetentionDays: 7,
   webServerEnabled: true,
   webServerPort: 4747,
@@ -179,6 +183,8 @@ const DEFAULTS: Required<
   userProfileCentroidDriftThreshold: 0.65,
   userProfileEmbeddingMinDescriptionLength: 5,
   userProfileMinEvidenceForRetention: 3,
+  userProfileAutoCleanupEnabled: true,
+  userProfileAutoCleanupInterval: 100,
   userProfileValidationEnabled: false,
   showAutoCaptureToasts: true,
   showUserProfileToasts: true,
@@ -410,6 +416,11 @@ const CONFIG_TEMPLATE = `{
 
   // Maximum number of times to retry capturing a prompt if it fails (due to network, API errors, etc.)
   "autoCaptureMaxRetries": 3,
+
+  // Maximum UTF-8 bytes for the auto-capture markdown context sent to the summary model.
+  // Prevents HTTP 400 context overflows on models with ~131K token windows (e.g. Groq Llama).
+  // Rough guide: tokens ≈ bytes / 4 for mixed code/prose.
+  "autoCaptureMaxContextBytes": 131072,
    
   // Days to keep AI session history before cleanup
   "aiSessionRetentionDays": 7,
@@ -488,6 +499,11 @@ const CONFIG_TEMPLATE = `{
   // Items confirmed fewer times are more likely to be pruned when confidence decays
   "userProfileMinEvidenceForRetention": 3,
 
+  // Periodically merge duplicate or irrelevant profile items with the configured AI provider
+  "userProfileAutoCleanupEnabled": true,
+  // Number of analyzed user prompts between automatic AI cleanup runs
+  "userProfileAutoCleanupInterval": 100,
+
   // Enable LLM validation of existing preferences against recent behavior.
   // When enabled, each analysis round checks if top-5 preferences still match recent prompts.
   // Experimental — disabled by default.
@@ -568,11 +584,23 @@ function getEmbeddingDimensions(model: string): number {
   return dimensionMap[model] || 768;
 }
 
+export function normalizeAutoCaptureMaxContextBytes(value: number): number {
+  if (!Number.isInteger(value) || value < 16384 || value > 16 * 1024 * 1024) {
+    throw new Error(`Invalid autoCaptureMaxContextBytes config: ${value}`);
+  }
+  return value;
+}
+
 function buildConfig(fileConfig: OpenCodeMemConfig) {
   const memoryApiKey = resolveSecretValue(fileConfig.memoryApiKey);
   const embeddingDimensions =
     fileConfig.embeddingDimensions ??
     getEmbeddingDimensions(fileConfig.embeddingModel ?? DEFAULTS.embeddingModel);
+  const autoCaptureMaxContextBytes = normalizeAutoCaptureMaxContextBytes(
+    fileConfig.autoCaptureMaxContextBytes ?? DEFAULTS.autoCaptureMaxContextBytes
+  );
+  const userProfileAutoCleanupInterval =
+    fileConfig.userProfileAutoCleanupInterval ?? DEFAULTS.userProfileAutoCleanupInterval;
 
   if (
     !Number.isInteger(embeddingDimensions) ||
@@ -581,6 +609,11 @@ function buildConfig(fileConfig: OpenCodeMemConfig) {
   ) {
     throw new Error(`Invalid embeddingDimensions config: ${embeddingDimensions}`);
   }
+  if (!Number.isInteger(userProfileAutoCleanupInterval) || userProfileAutoCleanupInterval <= 0) {
+    throw new Error(
+      `Invalid userProfileAutoCleanupInterval config: ${userProfileAutoCleanupInterval}`
+    );
+  }
 
   return {
     storagePath: expandPath(fileConfig.storagePath ?? DEFAULTS.storagePath),
@@ -605,6 +638,7 @@ function buildConfig(fileConfig: OpenCodeMemConfig) {
     autoCaptureIterationTimeout:
       fileConfig.autoCaptureIterationTimeout ?? DEFAULTS.autoCaptureIterationTimeout,
     autoCaptureMaxRetries: fileConfig.autoCaptureMaxRetries ?? DEFAULTS.autoCaptureMaxRetries,
+    autoCaptureMaxContextBytes,
     autoCaptureLanguage: fileConfig.autoCaptureLanguage,
     memoryProvider: (fileConfig.memoryProvider ?? "openai-chat") as
       "openai-chat" | "openai-responses" | "anthropic" | "minimax",
@@ -677,6 +711,9 @@ function buildConfig(fileConfig: OpenCodeMemConfig) {
       DEFAULTS.userProfileEmbeddingMinDescriptionLength,
     userProfileMinEvidenceForRetention:
       fileConfig.userProfileMinEvidenceForRetention ?? DEFAULTS.userProfileMinEvidenceForRetention,
+    userProfileAutoCleanupEnabled:
+      fileConfig.userProfileAutoCleanupEnabled ?? DEFAULTS.userProfileAutoCleanupEnabled,
+    userProfileAutoCleanupInterval,
     userProfileValidationEnabled:
       fileConfig.userProfileValidationEnabled ?? DEFAULTS.userProfileValidationEnabled,
     userProfileStaleDays: fileConfig.userProfileStaleDays ?? DEFAULTS.userProfileStaleDays,
 
@@ -54,6 +54,92 @@ function extractSessionTitle(response: unknown): string | undefined {
   return obj.data?.title ?? obj.title;
 }
 
+function unwrapSdkData<T>(response: unknown): T | undefined {
+  if (!response || typeof response !== "object") return undefined;
+  const obj = response as { data?: T };
+  return (obj.data ?? response) as T;
+}
+
+/**
+ * Resolve the session's active agent so compaction memory injection does not
+ * reset OpenCode to the stock "general-purpose" fallback (issue #236).
+ *
+ * Preference order:
+ * 1. session.get().agent (v2 hosts)
+ * 2. Latest non-compaction user message agent
+ * 3. Latest non-compaction / non-summary assistant mode (v1) or agent (v2)
+ */
+export async function resolveSessionAgent(
+  client: unknown,
+  sessionID: string
+): Promise<string | undefined> {
+  const sessionClient = (
+    client as {
+      session?: {
+        get?: (args: unknown) => Promise<unknown>;
+        messages?: (args: unknown) => Promise<unknown>;
+      };
+    }
+  )?.session;
+
+  if (typeof sessionClient?.get === "function") {
+    try {
+      const session = unwrapSdkData<{ agent?: string }>(
+        await sessionClient.get({ path: { id: sessionID } })
+      );
+      if (typeof session?.agent === "string" && session.agent.trim()) {
+        return session.agent.trim();
+      }
+    } catch (error) {
+      log("resolveSessionAgent: session.get failed", { sessionID, error: String(error) });
+    }
+  }
+
+  if (typeof sessionClient?.messages !== "function") {
+    return undefined;
+  }
+
+  try {
+    const messages = unwrapSdkData<
+      Array<{
+        info?: {
+          role?: string;
+          agent?: string;
+          mode?: string;
+          summary?: boolean;
+        };
+      }>
+    >(await sessionClient.messages({ path: { id: sessionID } }));
+
+    if (!Array.isArray(messages)) return undefined;
+
+    for (let i = messages.length - 1; i >= 0; i--) {
+      const info = messages[i]?.info;
+      if (!info) continue;
+
+      if (info.role === "user") {
+        if (typeof info.agent === "string" && info.agent.trim()) {
+          return info.agent.trim();
+        }
+        continue;
+      }
+
+      if (info.role === "assistant") {
+        if (info.summary === true || info.mode === "compaction") continue;
+        const agent =
+          (typeof info.agent === "string" && info.agent.trim()) ||
+          (typeof info.mode === "string" && info.mode.trim()) ||
+          undefined;
+        if (agent) return agent;
+      }
+    }
+  } catch (error) {
+    log("resolveSessionAgent: session.messages failed", { sessionID, error: String(error) });
+  }
+
+  return undefined;
+}
+
 async function isInternalCaptureSession(client: unknown, sessionID: string): Promise<boolean> {
   // Fast path: sessions we created ourselves (survives brief post-delete window).
   if (isTrackedInternalCaptureSession(sessionID)) {
@@ -873,12 +959,23 @@ export const OpenCodeMemPlugin: Plugin = async (ctx: PluginInput) => {
           }
 
           const memoryContext = formatMemoriesForCompaction(memoriesResult.results);
+          const agent = await resolveSessionAgent(ctx.client, sessionID);
+          if (!agent) {
+            log(
+              "Compaction: skipped memory injection because session agent could not be resolved",
+              {
+                sessionID,
+              }
+            );
+            return;
+          }
 
           await ctx.client.session.prompt({
             path: { id: sessionID },
             body: {
               parts: [{ id: `prt-compaction-${Date.now()}`, type: "text", text: memoryContext }],
               noReply: true,
+              agent,
             },
           });
 
@@ -898,6 +995,7 @@ export const OpenCodeMemPlugin: Plugin = async (ctx: PluginInput) => {
           log("Compaction memory injected", {
             sessionID,
             count: memoriesResult.results.length,
+            agent: agent ?? null,
           });
         } catch (error) {
           log("Compaction handler error", { error: String(error) });
 
@@ -62,8 +62,13 @@ export class UserProfileValidator {
       if (!pref.description || typeof pref.description !== "string") {
         errors.push(`preferences[${i}].description is missing or invalid`);
       }
-      if (typeof pref.confidence !== "number") {
-        errors.push(`preferences[${i}].confidence is missing or invalid`);
+      if (
+        typeof pref.confidence !== "number" ||
+        !Number.isFinite(pref.confidence) ||
+        pref.confidence < 0 ||
+        pref.confidence > 1
+      ) {
+        errors.push(`preferences[${i}].confidence must be a finite number between 0 and 1`);
       }
       if (!Array.isArray(pref.evidence)) {
         errors.push(`preferences[${i}].evidence must be an array`);