diff --git a/server/src/llm/providers/claude_code.rs b/server/src/llm/providers/claude_code.rs
index 5347c13..ea8f4fe 100644
--- a/server/src/llm/providers/claude_code.rs
+++ b/server/src/llm/providers/claude_code.rs
@@ -226,53 +226,9 @@ fn run_pty_session(
 
                 // Try to parse as JSON
                 if let Ok(json) = serde_json::from_str::<serde_json::Value>(trimmed)
-                    && let Some(event_type) = json.get("type").and_then(|t| t.as_str())
+                    && process_json_event(&json, &token_tx, &msg_tx, &mut sid_tx)
                 {
-                    // Capture session_id from any event that has it
-                    if let Some(tx) = sid_tx.take() {
-                        if let Some(sid) = json.get("session_id").and_then(|s| s.as_str()) {
-                            let _ = tx.send(sid.to_string());
-                        } else {
-                            // Put it back if this event didn't have a session_id
-                            sid_tx = Some(tx);
-                        }
-                    }
-
-                    match event_type {
-                        // Streaming deltas — used for real-time text display only
-                        "stream_event" => {
-                            if let Some(event) = json.get("event") {
-                                handle_stream_event(event, &token_tx);
-                            }
-                        }
-                        // Complete assistant message — extract text and tool_use blocks
-                        "assistant" => {
-                            if let Some(message) = json.get("message")
-                                && let Some(content) =
-                                    message.get("content").and_then(|c| c.as_array())
-                            {
-                                parse_assistant_message(content, &msg_tx);
-                            }
-                        }
-                        // User message containing tool results from Claude Code's own execution
-                        "user" => {
-                            if let Some(message) = json.get("message")
-                                && let Some(content) =
-                                    message.get("content").and_then(|c| c.as_array())
-                            {
-                                parse_tool_results(content, &msg_tx);
-                            }
-                        }
-                        // Final result with usage stats
-                        "result" => {
-                            got_result = true;
-                        }
-                        // System init — suppress noisy model/apiKey notification
-                        "system" => {}
-                        // Rate limit info — suppress noisy notification
-                        "rate_limit_event" => {}
-                        _ => {}
-                    }
+                    got_result = true;
                 }
                 // Ignore non-JSON lines (terminal escape sequences)
 
@@ -287,36 +243,8 @@ fn run_pty_session(
                     // Drain remaining lines
                     while let Ok(Some(line)) = line_rx.try_recv() {
                         let trimmed = line.trim();
-                        if let Ok(json) = serde_json::from_str::<serde_json::Value>(trimmed)
-                            && let Some(event_type) =
-                                json.get("type").and_then(|t| t.as_str())
-                        {
-                            match event_type {
-                                "stream_event" => {
-                                    if let Some(event) = json.get("event") {
-                                        handle_stream_event(event, &token_tx);
-                                    }
-                                }
-                                "assistant" => {
-                                    if let Some(message) = json.get("message")
-                                        && let Some(content) = message
-                                            .get("content")
-                                            .and_then(|c| c.as_array())
-                                    {
-                                        parse_assistant_message(content, &msg_tx);
-                                    }
-                                }
-                                "user" => {
-                                    if let Some(message) = json.get("message")
-                                        && let Some(content) = message
-                                            .get("content")
-                                            .and_then(|c| c.as_array())
-                                    {
-                                        parse_tool_results(content, &msg_tx);
-                                    }
-                                }
-                                _ => {}
-                            }
+                        if let Ok(json) = serde_json::from_str::<serde_json::Value>(trimmed) {
+                            process_json_event(&json, &token_tx, &msg_tx, &mut sid_tx);
                         }
                     }
                     break;
@@ -349,6 +277,59 @@ fn run_pty_session(
     Ok(())
 }
 
+/// Dispatch a single parsed JSON event to the appropriate handler.
+///
+/// Returns `true` if a `result` event was received (signals session completion).
+/// Captures the session ID from the first event that carries it.
+fn process_json_event(
+    json: &serde_json::Value,
+    token_tx: &tokio::sync::mpsc::UnboundedSender<String>,
+    msg_tx: &std::sync::mpsc::Sender<Message>,
+    sid_tx: &mut Option<tokio::sync::oneshot::Sender<String>>,
+) -> bool {
+    let event_type = match json.get("type").and_then(|t| t.as_str()) {
+        Some(t) => t,
+        None => return false,
+    };
+
+    // Capture session_id from the first event that carries it
+    if let Some(tx) = sid_tx.take() {
+        if let Some(sid) = json.get("session_id").and_then(|s| s.as_str()) {
+            let _ = tx.send(sid.to_string());
+        } else {
+            *sid_tx = Some(tx);
+        }
+    }
+
+    match event_type {
+        "stream_event" => {
+            if let Some(event) = json.get("event") {
+                handle_stream_event(event, token_tx);
+            }
+            false
+        }
+        "assistant" => {
+            if let Some(message) = json.get("message")
+                && let Some(content) = message.get("content").and_then(|c| c.as_array())
+            {
+                parse_assistant_message(content, msg_tx);
+            }
+            false
+        }
+        "user" => {
+            if let Some(message) = json.get("message")
+                && let Some(content) = message.get("content").and_then(|c| c.as_array())
+            {
+                parse_tool_results(content, msg_tx);
+            }
+            false
+        }
+        "result" => true,
+        // system, rate_limit_event, and unknown types are no-ops
+        _ => false,
+    }
+}
+
 /// Parse a complete `assistant` message content array.
 ///
 /// Extracts text blocks into `content` and tool_use blocks into `tool_calls`,
@@ -669,4 +650,298 @@ mod tests {
         };
         assert!(tokens.is_empty());
     }
+
+    #[test]
+    fn handle_stream_event_thinking_delta_sends_prefixed_token() {
+        let (tx, mut rx) = tokio::sync::mpsc::unbounded_channel();
+        let event = json!({
+            "type": "content_block_delta",
+            "delta": {"type": "thinking_delta", "thinking": "I should check the file"}
+        });
+        handle_stream_event(&event, &tx);
+        drop(tx);
+        let tokens: Vec<String> = {
+            let mut v = vec![];
+            while let Ok(t) = rx.try_recv() {
+                v.push(t);
+            }
+            v
+        };
+        assert_eq!(tokens, vec!["[thinking] I should check the file"]);
+    }
+
+    #[test]
+    fn handle_stream_event_error_sends_error_token() {
+        let (tx, mut rx) = tokio::sync::mpsc::unbounded_channel();
+        let event = json!({
+            "type": "error",
+            "error": {"type": "overloaded_error", "message": "Overloaded"}
+        });
+        handle_stream_event(&event, &tx);
+        drop(tx);
+        let tokens: Vec<String> = {
+            let mut v = vec![];
+            while let Ok(t) = rx.try_recv() {
+                v.push(t);
+            }
+            v
+        };
+        assert_eq!(tokens, vec!["\n[error: Overloaded]\n"]);
+    }
+
+    #[test]
+    fn handle_stream_event_unknown_type_is_noop() {
+        let (tx, mut rx) = tokio::sync::mpsc::unbounded_channel();
+        let event = json!({"type": "ping"});
+        handle_stream_event(&event, &tx);
+        drop(tx);
+        let tokens: Vec<String> = {
+            let mut v = vec![];
+            while let Ok(t) = rx.try_recv() {
+                v.push(t);
+            }
+            v
+        };
+        assert!(tokens.is_empty());
+    }
+
+    #[test]
+    fn parse_tool_results_no_tool_use_id() {
+        let content = vec![json!({"type": "tool_result", "content": "output"})];
+        let msgs = collect_messages(|tx| parse_tool_results(&content, tx));
+        assert_eq!(msgs.len(), 1);
+        assert!(msgs[0].tool_call_id.is_none());
+        assert_eq!(msgs[0].content, "output");
+    }
+
+    #[test]
+    fn parse_tool_results_null_content() {
+        let content = vec![json!({"type": "tool_result", "tool_use_id": "id1"})];
+        let msgs = collect_messages(|tx| parse_tool_results(&content, tx));
+        assert_eq!(msgs.len(), 1);
+        assert_eq!(msgs[0].content, "");
+    }
+
+    #[test]
+    fn parse_tool_results_other_json_content() {
+        let content = vec![json!({
+            "type": "tool_result",
+            "tool_use_id": "id1",
+            "content": {"nested": "object"}
+        })];
+        let msgs = collect_messages(|tx| parse_tool_results(&content, tx));
+        assert_eq!(msgs.len(), 1);
+        // Falls through to serde_json::to_string
+        assert!(!msgs[0].content.is_empty());
+    }
+
+    #[test]
+    fn parse_assistant_message_empty_content_array() {
+        let content: Vec<serde_json::Value> = vec![];
+        let msgs = collect_messages(|tx| parse_assistant_message(&content, tx));
+        assert_eq!(msgs.len(), 1);
+        assert_eq!(msgs[0].content, "");
+        assert!(msgs[0].tool_calls.is_none());
+    }
+
+    #[test]
+    fn parse_assistant_message_unknown_block_type() {
+        let content = vec![
+            json!({"type": "image", "source": {"type": "base64"}}),
+            json!({"type": "text", "text": "done"}),
+        ];
+        let msgs = collect_messages(|tx| parse_assistant_message(&content, tx));
+        assert_eq!(msgs.len(), 1);
+        assert_eq!(msgs[0].content, "done");
+    }
+
+    #[test]
+    fn parse_assistant_message_tool_use_without_id() {
+        let content = vec![json!({
+            "type": "tool_use",
+            "name": "Bash",
+            "input": {"command": "ls"}
+        })];
+        let msgs = collect_messages(|tx| parse_assistant_message(&content, tx));
+        assert_eq!(msgs.len(), 1);
+        let calls = msgs[0].tool_calls.as_ref().unwrap();
+        assert_eq!(calls.len(), 1);
+        assert!(calls[0].id.is_none());
+        assert_eq!(calls[0].function.name, "Bash");
+    }
+
+    #[test]
+    fn parse_assistant_message_tool_use_without_input_defaults_to_empty_object() {
+        let content = vec![json!({"type": "tool_use", "id": "tid", "name": "Read"})];
+        let msgs = collect_messages(|tx| parse_assistant_message(&content, tx));
+        let calls = msgs[0].tool_calls.as_ref().unwrap();
+        let args: serde_json::Value = serde_json::from_str(&calls[0].function.arguments).unwrap();
+        assert!(args.is_object());
+        assert!(args.as_object().unwrap().is_empty());
+    }
+
+    fn make_channels() -> (
+        tokio::sync::mpsc::UnboundedSender<String>,
+        tokio::sync::mpsc::UnboundedReceiver<String>,
+        std::sync::mpsc::Sender<Message>,
+        std::sync::mpsc::Receiver<Message>,
+    ) {
+        let (tok_tx, tok_rx) = tokio::sync::mpsc::unbounded_channel();
+        let (msg_tx, msg_rx) = std::sync::mpsc::channel();
+        (tok_tx, tok_rx, msg_tx, msg_rx)
+    }
+
+    #[test]
+    fn process_json_event_result_returns_true() {
+        let (tok_tx, _tok_rx, msg_tx, _msg_rx) = make_channels();
+        let (sid_tx, _sid_rx) = tokio::sync::oneshot::channel::<String>();
+        let mut sid_tx_opt = Some(sid_tx);
+        let json = json!({"type": "result", "subtype": "success"});
+        assert!(process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx_opt));
+    }
+
+    #[test]
+    fn process_json_event_system_returns_false() {
+        let (tok_tx, _tok_rx, msg_tx, _msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({"type": "system", "subtype": "init", "apiKeySource": "env"});
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+    }
+
+    #[test]
+    fn process_json_event_rate_limit_returns_false() {
+        let (tok_tx, _tok_rx, msg_tx, _msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({"type": "rate_limit_event"});
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+    }
+
+    #[test]
+    fn process_json_event_unknown_type_returns_false() {
+        let (tok_tx, _tok_rx, msg_tx, _msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({"type": "some_future_event"});
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+    }
+
+    #[test]
+    fn process_json_event_no_type_returns_false() {
+        let (tok_tx, _tok_rx, msg_tx, _msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({"content": "no type field"});
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+    }
+
+    #[test]
+    fn process_json_event_captures_session_id() {
+        let (tok_tx, _tok_rx, msg_tx, _msg_rx) = make_channels();
+        let (sid_tx, mut sid_rx) = tokio::sync::oneshot::channel::<String>();
+        let mut sid_tx_opt = Some(sid_tx);
+        let json = json!({"type": "system", "session_id": "sess-abc-123"});
+        process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx_opt);
+        // sid_tx should have been consumed
+        assert!(sid_tx_opt.is_none());
+        let received = sid_rx.try_recv().unwrap();
+        assert_eq!(received, "sess-abc-123");
+    }
+
+    #[test]
+    fn process_json_event_preserves_sid_tx_if_no_session_id() {
+        let (tok_tx, _tok_rx, msg_tx, _msg_rx) = make_channels();
+        let (sid_tx, _sid_rx) = tokio::sync::oneshot::channel::<String>();
+        let mut sid_tx_opt = Some(sid_tx);
+        let json = json!({"type": "system"});
+        process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx_opt);
+        // sid_tx should still be present since no session_id in event
+        assert!(sid_tx_opt.is_some());
+    }
+
+    #[test]
+    fn process_json_event_stream_event_forwards_token() {
+        let (tok_tx, mut tok_rx, msg_tx, _msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({
+            "type": "stream_event",
+            "session_id": "s1",
+            "event": {
+                "type": "content_block_delta",
+                "delta": {"type": "text_delta", "text": "word"}
+            }
+        });
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+        drop(tok_tx);
+        let tokens: Vec<String> = {
+            let mut v = vec![];
+            while let Ok(t) = tok_rx.try_recv() {
+                v.push(t);
+            }
+            v
+        };
+        assert_eq!(tokens, vec!["word"]);
+    }
+
+    #[test]
+    fn process_json_event_assistant_event_parses_message() {
+        let (tok_tx, _tok_rx, msg_tx, msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({
+            "type": "assistant",
+            "message": {
+                "content": [{"type": "text", "text": "Hi!"}]
+            }
+        });
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+        drop(msg_tx);
+        let msgs: Vec<Message> = msg_rx.try_iter().collect();
+        assert_eq!(msgs.len(), 1);
+        assert_eq!(msgs[0].content, "Hi!");
+    }
+
+    #[test]
+    fn process_json_event_user_event_parses_tool_results() {
+        let (tok_tx, _tok_rx, msg_tx, msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({
+            "type": "user",
+            "message": {
+                "content": [{"type": "tool_result", "tool_use_id": "tid1", "content": "done"}]
+            }
+        });
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+        drop(msg_tx);
+        let msgs: Vec<Message> = msg_rx.try_iter().collect();
+        assert_eq!(msgs.len(), 1);
+        assert_eq!(msgs[0].role, Role::Tool);
+        assert_eq!(msgs[0].content, "done");
+    }
+
+    #[test]
+    fn process_json_event_assistant_without_content_array_is_noop() {
+        let (tok_tx, _tok_rx, msg_tx, msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({
+            "type": "assistant",
+            "message": {"content": "not an array"}
+        });
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+        drop(msg_tx);
+        let msgs: Vec<Message> = msg_rx.try_iter().collect();
+        assert!(msgs.is_empty());
+    }
+
+    #[test]
+    fn process_json_event_user_without_content_array_is_noop() {
+        let (tok_tx, _tok_rx, msg_tx, msg_rx) = make_channels();
+        let mut sid_tx = None::<tokio::sync::oneshot::Sender<String>>;
+        let json = json!({"type": "user", "message": {"content": null}});
+        assert!(!process_json_event(&json, &tok_tx, &msg_tx, &mut sid_tx));
+        drop(msg_tx);
+        let msgs: Vec<Message> = msg_rx.try_iter().collect();
+        assert!(msgs.is_empty());
+    }
+
+    #[test]
+    fn claude_code_provider_new() {
+        let _provider = ClaudeCodeProvider::new();
+    }
 }