feat: implement SDK session ID handling for conversation continuity

- Added support for resuming conversations using the Claude SDK session ID.
- Updated the ClaudeProvider to conditionally resume sessions based on the presence of a session ID and conversation history.
- Enhanced the AgentService to capture and store the SDK session ID from incoming messages, ensuring continuity in conversations.

apps/server/src/providers/claude-provider.ts

@@ -7,10 +7,6 @@
 
 import { query, type Options } from "@anthropic-ai/claude-agent-sdk";
 import { BaseProvider } from "./base-provider.js";
-import {
-  convertHistoryToMessages,
-  normalizeContentBlocks,
-} from "../lib/conversation-utils.js";
 import type {
   ExecuteOptions,
   ProviderMessage,
@@ -38,6 +34,7 @@ export class ClaudeProvider extends BaseProvider {
       allowedTools,
       abortController,
       conversationHistory,
+      sdkSessionId,
     } = options;
 
     // Build Claude SDK options
@@ -65,69 +62,17 @@ export class ClaudeProvider extends BaseProvider {
         autoAllowBashIfSandboxed: true,
       },
       abortController,
+      // Resume existing SDK session if we have a session ID
+      ...(sdkSessionId && conversationHistory && conversationHistory.length > 0
+        ? { resume: sdkSessionId }
+        : {}),
     };
 
-    // Build prompt payload with conversation history
-    let promptPayload: string | AsyncGenerator<any, void, unknown> | Array<any>;
+    // Build prompt payload
+    let promptPayload: string | AsyncIterable<any>;
 
-    if (conversationHistory && conversationHistory.length > 0) {
-      // Multi-turn conversation with history
-      // Convert history to SDK message format
-      // Note: When using async generator, SDK only accepts SDKUserMessage (type: 'user')
-      // So we filter to only include user messages to avoid SDK errors
-      const historyMessages = convertHistoryToMessages(conversationHistory);
-      const hasAssistantMessages = historyMessages.some(
-        (msg) => msg.type === "assistant"
-      );
-
-      if (hasAssistantMessages) {
-        // If we have assistant messages, use async generator but filter to only user messages
-        // This maintains conversation flow while respecting SDK type constraints
-        promptPayload = (async function* () {
-          // Filter to only user messages - SDK async generator only accepts SDKUserMessage
-          const userHistoryMessages = historyMessages.filter(
-            (msg) => msg.type === "user"
-          );
-          for (const msg of userHistoryMessages) {
-            yield msg;
-          }
-
-          // Yield current prompt
-          const normalizedPrompt = normalizeContentBlocks(prompt);
-          const currentPrompt = {
-            type: "user" as const,
-            session_id: "",
-            message: {
-              role: "user" as const,
-              content: normalizedPrompt,
-            },
-            parent_tool_use_id: null,
-          };
-          yield currentPrompt;
-        })();
-      } else {
-        // Only user messages in history - can use async generator normally
-        promptPayload = (async function* () {
-          for (const msg of historyMessages) {
-            yield msg;
-          }
-
-          // Yield current prompt
-          const normalizedPrompt = normalizeContentBlocks(prompt);
-          const currentPrompt = {
-            type: "user" as const,
-            session_id: "",
-            message: {
-              role: "user" as const,
-              content: normalizedPrompt,
-            },
-            parent_tool_use_id: null,
-          };
-          yield currentPrompt;
-        })();
-      }
-    } else if (Array.isArray(prompt)) {
-      // Multi-part prompt (with images) - no history
+    if (Array.isArray(prompt)) {
+      // Multi-part prompt (with images)
       promptPayload = (async function* () {
         const multiPartPrompt = {
           type: "user" as const,
@@ -141,7 +86,7 @@ export class ClaudeProvider extends BaseProvider {
         yield multiPartPrompt;
       })();
     } else {
-      // Simple text prompt - no history
+      // Simple text prompt
       promptPayload = prompt;
     }
 

apps/server/src/providers/types.ts

@@ -32,6 +32,7 @@ export interface ExecuteOptions {
   mcpServers?: Record<string, unknown>;
   abortController?: AbortController;
   conversationHistory?: ConversationMessage[]; // Previous messages for context
+  sdkSessionId?: string; // Claude SDK session ID for resuming conversations
 }
 
 /**

apps/server/src/services/agent-service.ts

@@ -33,6 +33,7 @@ interface Session {
   abortController: AbortController | null;
   workingDirectory: string;
   model?: string;
+  sdkSessionId?: string; // Claude SDK session ID for conversation continuity
 }
 
 interface SessionMetadata {
@@ -200,6 +201,7 @@ export class AgentService {
         abortController: session.abortController!,
         conversationHistory:
           conversationHistory.length > 0 ? conversationHistory : undefined,
+        sdkSessionId: session.sdkSessionId, // Pass SDK session ID for resuming
       };
 
       // Build prompt content with images
@@ -221,6 +223,14 @@ export class AgentService {
       const toolUses: Array<{ name: string; input: unknown }> = [];
 
       for await (const msg of stream) {
+        // Capture SDK session ID from any message
+        if (msg.session_id && !session.sdkSessionId) {
+          session.sdkSessionId = msg.session_id;
+          console.log(
+            `[AgentService] Captured SDK session ID: ${msg.session_id}`
+          );
+        }
+
         if (msg.type === "assistant") {
           if (msg.message?.content) {
             for (const block of msg.message.content) {