diff --git a/extensions/qqbot/src/engine/utils/string-normalize.ts b/extensions/qqbot/src/engine/utils/string-normalize.ts
index 491479e78c6..40a7d08630a 100644
--- a/extensions/qqbot/src/engine/utils/string-normalize.ts
+++ b/extensions/qqbot/src/engine/utils/string-normalize.ts
@@ -49,23 +49,8 @@ export function normalizeLowercaseStringOrEmpty(value: unknown): string {
   return normalizeOptionalLowercaseString(value) ?? "";
 }
 
-/** Return the raw string value or `undefined`. No trimming. */
-export function readStringValue(value: unknown): string | undefined {
-  return typeof value === "string" ? value : undefined;
-}
-
-/** Return true when the value is a non-empty trimmed string. */
-export function hasNonEmptyString(value: unknown): value is string {
-  return normalizeOptionalString(value) !== undefined;
-}
-
 // ---- Record coercion ----
 
-/** Coerce a value into a `Record<string, unknown>`, defaulting to `{}`. */
-export function asRecord(value: unknown): Record<string, unknown> {
-  return typeof value === "object" && value !== null ? (value as Record<string, unknown>) : {};
-}
-
 /** Coerce a value into a `Record<string, unknown>` or `undefined`. */
 export function asOptionalObjectRecord(value: unknown): Record<string, unknown> | undefined {
   return value && typeof value === "object" ? (value as Record<string, unknown>) : undefined;
@@ -80,37 +65,6 @@ export function readStringField(
   return typeof v === "string" ? v : undefined;
 }
 
-/** Read a number field from a record. */
-export function readNumberField(
-  record: Record<string, unknown> | null | undefined,
-  key: string,
-): number | undefined {
-  const v = record?.[key];
-  return typeof v === "number" ? v : undefined;
-}
-
-/** Read a boolean field from a record. */
-export function readBooleanField(
-  record: Record<string, unknown> | null | undefined,
-  key: string,
-): boolean | undefined {
-  const v = record?.[key];
-  return typeof v === "boolean" ? v : undefined;
-}
-
-/** Coerce a value into a string→string map, filtering out non-string values. */
-export function readStringMap(value: unknown): Record<string, string> {
-  const record = asOptionalObjectRecord(value);
-  if (!record) {
-    return {};
-  }
-  return Object.fromEntries(
-    Object.entries(record).flatMap(([key, entryValue]) =>
-      typeof entryValue === "string" ? [[key, entryValue]] : [],
-    ),
-  );
-}
-
 // ---- Filename normalization ----
 
 /**
diff --git a/extensions/qqbot/src/engine/utils/text-chunk.ts b/extensions/qqbot/src/engine/utils/text-chunk.ts
index 577d153da2e..c13e1a3c5e5 100644
--- a/extensions/qqbot/src/engine/utils/text-chunk.ts
+++ b/extensions/qqbot/src/engine/utils/text-chunk.ts
@@ -12,9 +12,6 @@
 /** Maximum text length for a single QQ Bot message. */
 export const TEXT_CHUNK_LIMIT = 5000;
 
-/** Text chunker function signature. */
-export type ChunkTextFn = (text: string, limit: number) => string[];
-
 /**
  * Naive text chunking fallback.
  *