diff --git a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChat.tsx b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChat.tsx
index ec6653801978..270f030a1b61 100644
--- a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChat.tsx
+++ b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChat.tsx
@@ -10,6 +10,7 @@ import {PlaygroundState} from '../types';
 import {PlaygroundCallStats} from './PlaygroundCallStats';
 import {PlaygroundChatInput} from './PlaygroundChatInput';
 import {PlaygroundChatTopBar} from './PlaygroundChatTopBar';
+import {useChatCompletionFunctions} from './useChatCompletionFunctions';
 import {
   SetPlaygroundStateFieldFunctionType,
   useChatFunctions,
@@ -35,10 +36,19 @@ export const PlaygroundChat = ({
   settingsTab,
 }: PlaygroundChatProps) => {
   const [chatText, setChatText] = useState('');
-  // eslint-disable-next-line @typescript-eslint/no-unused-vars
   const [isLoading, setIsLoading] = useState(false);
   const chatPercentWidth = 100 / playgroundStates.length;
 
+  const {handleRetry, handleSend} = useChatCompletionFunctions(
+    setPlaygroundStates,
+    setIsLoading,
+    chatText,
+    playgroundStates,
+    entity,
+    project,
+    setChatText
+  );
+
   const {deleteMessage, editMessage, deleteChoice, editChoice, addMessage} =
     useChatFunctions(setPlaygroundStateField);
 
@@ -145,18 +155,14 @@ export const PlaygroundChat = ({
                           editChoice: (choiceIndex, newChoice) =>
                             editChoice(idx, choiceIndex, newChoice),
                           retry: (messageIndex: number, isChoice?: boolean) =>
-                            console.log('retry', messageIndex, isChoice),
+                            handleRetry(idx, messageIndex, isChoice),
                           sendMessage: (
                             role: 'assistant' | 'user' | 'tool',
                             content: string,
                             toolCallId?: string
-                          ) =>
-                            console.log(
-                              'sendMessage',
-                              role,
-                              content,
-                              toolCallId
-                            ),
+                          ) => {
+                            handleSend(role, idx, content, toolCallId);
+                          },
                         }}>
                         <CallChat call={state.traceCall as TraceCallSchema} />
                       </PlaygroundContext.Provider>
@@ -187,7 +193,7 @@ export const PlaygroundChat = ({
         chatText={chatText}
         setChatText={setChatText}
         isLoading={isLoading}
-        onSend={() => {}}
+        onSend={handleSend}
         onAdd={handleAddMessage}
       />
     </Box>
diff --git a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChatTopBar.tsx b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChatTopBar.tsx
index 2fcd24f56e3a..7e1b4b13bb13 100644
--- a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChatTopBar.tsx
+++ b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/PlaygroundChatTopBar.tsx
@@ -79,7 +79,7 @@ export const PlaygroundChatTopBar: React.FC<PlaygroundChatTopBarProps> = ({
           display: 'flex',
           gap: '8px',
           alignItems: 'center',
-          backgroundColor: 'white',
+          backgroundColor: 'transparent',
         }}>
         {!onlyOneChat && <Tag label={`${idx + 1}`} />}
         <LLMDropdown
@@ -97,7 +97,7 @@ export const PlaygroundChatTopBar: React.FC<PlaygroundChatTopBarProps> = ({
           display: 'flex',
           alignItems: 'center',
           gap: '4px',
-          backgroundColor: 'white',
+          backgroundColor: 'transparent',
         }}>
         <Button
           tooltip={'Clear chat'}
diff --git a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/useChatCompletionFunctions.tsx b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/useChatCompletionFunctions.tsx
new file mode 100644
index 000000000000..3d902f54a72b
--- /dev/null
+++ b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/useChatCompletionFunctions.tsx
@@ -0,0 +1,219 @@
+import {toast} from '@wandb/weave/common/components/elements/Toast';
+import React from 'react';
+import {Link} from 'react-router-dom';
+
+import {Message} from '../../ChatView/types';
+import {useGetTraceServerClientContext} from '../../wfReactInterface/traceServerClientContext';
+import {CompletionsCreateRes} from '../../wfReactInterface/traceServerClientTypes';
+import {PlaygroundState} from '../types';
+import {getInputFromPlaygroundState} from '../usePlaygroundState';
+import {clearTraceCall} from './useChatFunctions';
+
+export const useChatCompletionFunctions = (
+  setPlaygroundStates: (states: PlaygroundState[]) => void,
+  setIsLoading: (isLoading: boolean) => void,
+  chatText: string,
+  playgroundStates: PlaygroundState[],
+  entity: string,
+  project: string,
+  setChatText: (text: string) => void
+) => {
+  const getTsClient = useGetTraceServerClientContext();
+
+  const makeCompletionRequest = async (
+    callIndex: number,
+    updatedStates: PlaygroundState[]
+  ): Promise<CompletionsCreateRes | null> => {
+    const inputs = getInputFromPlaygroundState(updatedStates[callIndex]);
+
+    return getTsClient().completionsCreate({
+      project_id: `${entity}/${project}`,
+      inputs,
+      track_llm_call: updatedStates[callIndex].trackLLMCall,
+    });
+  };
+
+  const handleErrorsAndUpdate = async (
+    response: Array<CompletionsCreateRes | null>,
+    updatedStates: PlaygroundState[],
+    callIndex?: number
+  ): Promise<boolean> => {
+    const hasMissingLLMApiKey = handleMissingLLMApiKey(response, entity);
+    const hasError = handleErrorResponse(response.map(r => r?.response));
+
+    if (hasMissingLLMApiKey || hasError) {
+      return false;
+    }
+
+    const finalStates = updatedStates.map((state, index) => {
+      if (callIndex === undefined || index === callIndex) {
+        return handleUpdateCallWithResponse(state, response[index]);
+      }
+      return state;
+    });
+
+    setPlaygroundStates(finalStates);
+    return true;
+  };
+
+  const handleSend = async (
+    role: 'assistant' | 'user' | 'tool',
+    callIndex?: number,
+    content?: string,
+    toolCallId?: string
+  ) => {
+    try {
+      setIsLoading(true);
+      const newMessage = createMessage(role, content || chatText, toolCallId);
+      const updatedStates = playgroundStates.map((state, index) => {
+        if (callIndex !== undefined && callIndex !== index) {
+          return state;
+        }
+        const updatedState = appendChoicesToMessages(state);
+        if (updatedState.traceCall?.inputs?.messages) {
+          updatedState.traceCall.inputs.messages.push(newMessage);
+        }
+        return updatedState;
+      });
+
+      setPlaygroundStates(updatedStates);
+      setChatText('');
+
+      const responses = await Promise.all(
+        updatedStates.map(async (_, index) => {
+          if (callIndex !== undefined && callIndex !== index) {
+            return Promise.resolve(null);
+          }
+          return await makeCompletionRequest(index, updatedStates);
+        })
+      );
+      await handleErrorsAndUpdate(responses, updatedStates);
+    } catch (error) {
+      console.error('Error processing completion:', error);
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  const handleRetry = async (
+    callIndex: number,
+    messageIndex: number,
+    isChoice?: boolean
+  ) => {
+    try {
+      setIsLoading(true);
+      const updatedStates = playgroundStates.map((state, index) => {
+        if (index === callIndex) {
+          if (isChoice) {
+            return appendChoicesToMessages(state);
+          }
+          const updatedState = JSON.parse(JSON.stringify(state));
+          if (updatedState.traceCall?.inputs?.messages) {
+            updatedState.traceCall.inputs.messages =
+              updatedState.traceCall.inputs.messages.slice(0, messageIndex + 1);
+          }
+          return updatedState;
+        }
+        return state;
+      });
+
+      const response = await makeCompletionRequest(callIndex, updatedStates);
+      await handleErrorsAndUpdate(
+        updatedStates.map(() => response),
+        updatedStates,
+        callIndex
+      );
+    } catch (error) {
+      console.error('Error processing completion:', error);
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  return {handleRetry, handleSend};
+};
+
+// Helper functions
+const createMessage = (
+  role: 'assistant' | 'user' | 'tool',
+  content: string,
+  toolCallId?: string
+): Message | undefined => {
+  return content.trim() ? {role, content, tool_call_id: toolCallId} : undefined;
+};
+
+const handleMissingLLMApiKey = (responses: any, entity: string): boolean => {
+  if (Array.isArray(responses)) {
+    responses.forEach((response: any) => {
+      handleMissingLLMApiKey(response, entity);
+    });
+  } else {
+    if (responses && responses.api_key && responses.reason) {
+      toast(
+        <div>
+          <div>{responses.reason}</div>
+          Please add your API key to{' '}
+          <Link to={`/${entity}/settings`}>Team secrets in settings</Link> to
+          use this LLM
+        </div>,
+        {
+          type: 'error',
+        }
+      );
+      return true;
+    }
+  }
+  return false;
+};
+
+const handleErrorResponse = (
+  responses: Array<CompletionsCreateRes | null | {error: string}>
+): boolean => {
+  if (!responses) {
+    return true;
+  }
+  if (responses.some(r => r && 'error' in r)) {
+    const errorResponse = responses.find(r => r && 'error' in r) as {
+      error: string;
+    };
+    toast(errorResponse?.error, {
+      type: 'error',
+    });
+    return true;
+  }
+
+  return false;
+};
+
+const handleUpdateCallWithResponse = (
+  updatedCall: PlaygroundState,
+  response: any
+): PlaygroundState => {
+  if (!response) {
+    return updatedCall;
+  }
+  return {
+    ...updatedCall,
+    traceCall: {
+      ...clearTraceCall(updatedCall.traceCall),
+      id: response.weave_call_id ?? '',
+      output: response.response,
+    },
+  };
+};
+
+const appendChoicesToMessages = (state: PlaygroundState): PlaygroundState => {
+  const updatedState = JSON.parse(JSON.stringify(state));
+  if (
+    updatedState.traceCall?.inputs?.messages &&
+    updatedState.traceCall.output?.choices
+  ) {
+    updatedState.traceCall.output.choices.forEach((choice: any) => {
+      if (choice.message) {
+        updatedState.traceCall.inputs.messages.push(choice.message);
+      }
+    });
+    updatedState.traceCall.output.choices = undefined;
+  }
+  return updatedState;
+};
diff --git a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/useChatFunctions.tsx b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/useChatFunctions.tsx
index 178752a71da9..46c47abab743 100644
--- a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/useChatFunctions.tsx
+++ b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundChat/useChatFunctions.tsx
@@ -1,7 +1,7 @@
 import {cloneDeep} from 'lodash';
 import {SetStateAction} from 'react';
 
-import {Choice, Message} from '../../ChatView/types';
+import {Message} from '../../ChatView/types';
 import {OptionalTraceCallSchema, PlaygroundState} from '../types';
 import {DEFAULT_SYSTEM_MESSAGE} from '../usePlaygroundState';
 type TraceCallOutput = {
@@ -109,7 +109,7 @@ export const useChatFunctions = (
   const editChoice = (
     callIndex: number,
     choiceIndex: number,
-    newChoice: Choice
+    newChoice: Message
   ) => {
     setPlaygroundStateField(callIndex, 'traceCall', prevTraceCall => {
       const newTraceCall = clearTraceCall(
@@ -128,10 +128,7 @@ export const useChatFunctions = (
         // Add the new choice as a message
         newTraceCall.inputs = newTraceCall.inputs ?? {};
         newTraceCall.inputs.messages = newTraceCall.inputs.messages ?? [];
-        newTraceCall.inputs.messages.push({
-          role: 'assistant',
-          content: newChoice.message?.content,
-        });
+        newTraceCall.inputs.messages.push(newChoice);
       }
       return newTraceCall;
     });
diff --git a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundContext.tsx b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundContext.tsx
index 14485ed2434d..ec16276bc469 100644
--- a/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundContext.tsx
+++ b/weave-js/src/components/PagePanelComponents/Home/Browse3/pages/PlaygroundPage/PlaygroundContext.tsx
@@ -1,6 +1,6 @@
 import {createContext, useContext} from 'react';
 
-import {Choice, Message} from '../ChatView/types';
+import {Message} from '../ChatView/types';
 
 export type PlaygroundContextType = {
   isPlayground: boolean;
@@ -8,7 +8,7 @@ export type PlaygroundContextType = {
   editMessage: (messageIndex: number, newMessage: Message) => void;
   deleteMessage: (messageIndex: number, responseIndexes?: number[]) => void;
 
-  editChoice: (choiceIndex: number, newChoice: Choice) => void;
+  editChoice: (choiceIndex: number, newChoice: Message) => void;
   deleteChoice: (choiceIndex: number) => void;
 
   retry: (messageIndex: number, isChoice?: boolean) => void;