diff --git a/packages/services/conversation-service/src/infrastructure/claude/claude-agent.service.ts b/packages/services/conversation-service/src/infrastructure/claude/claude-agent.service.ts
index 6a23155..bc52b63 100644
--- a/packages/services/conversation-service/src/infrastructure/claude/claude-agent.service.ts
+++ b/packages/services/conversation-service/src/infrastructure/claude/claude-agent.service.ts
@@ -370,7 +370,7 @@ export class ClaudeAgentService implements OnModuleInit {
           totalInputTokens += finalMsg.usage.input_tokens || 0;
           totalOutputTokens += finalMsg.usage.output_tokens || 0;
           // Prompt Caching 的 tokens (如果 API 返回)
-          const usage = finalMsg.usage as Record<string, number>;
+          const usage = finalMsg.usage as unknown as Record<string, number>;
           totalCacheCreationTokens += usage.cache_creation_input_tokens || 0;
           totalCacheReadTokens += usage.cache_read_input_tokens || 0;
         }
diff --git a/packages/services/conversation-service/src/infrastructure/claude/token-usage.service.ts b/packages/services/conversation-service/src/infrastructure/claude/token-usage.service.ts
index bb0fe4d..9a487dc 100644
--- a/packages/services/conversation-service/src/infrastructure/claude/token-usage.service.ts
+++ b/packages/services/conversation-service/src/infrastructure/claude/token-usage.service.ts
@@ -11,7 +11,14 @@ import { TokenUsageEntity } from '../../domain/entities/token-usage.entity';
  * - Cache write: $3.75/MTok
  * - Cache read: $0.30/MTok
  */
-const PRICING = {
+interface PricingTier {
+  input: number;
+  output: number;
+  cacheWrite: number;
+  cacheRead: number;
+}
+
+const PRICING: Record<string, PricingTier> = {
   'claude-sonnet-4-20250514': {
     input: 3 / 1_000_000,
     output: 15 / 1_000_000,