```                   # 📋 Session Report
    λλ              
   λ⊙λ⊙             
  λλλλλλ            
 λλλλλλλλ           
    λλ              
    λλ              
    λλ              
    λλ              
    λλ              
    λλ              
    λλ              
    λλ              
```                 

**🔑 Session ID:** fdb82844-8df5-4a1c-8ca2-ac4a17d19462

---

## 📊 Statistics

### Turn Counts

| Metric | Value |
|--------|-------|
| Total Turns | 22 |
| 👤 User Turns | 11 |
| 🤖 LLM Turns | 11 |

### 🔧 Tool Calls

**Total Tool Calls:** 12

`bash_read-file      `    4 ████████████████████████████████████████████████████████████

`bash_check-code     `    3 █████████████████████████████████████████████

`bash_write-file     `    3 █████████████████████████████████████████████

`bash_grep-files     `    1 ███████████████

`bash_list-files     `    1 ███████████████


### 💾 Byte Usage

`Input     `    133 KiB ████████████████████████████████████████████████████████████

`Output    `      3 KiB █

`Reasoning `      3 KiB █
**Total:** 140 KiB

---

## 👤 Step 1: User Turn

### 📝 System Prompt

```
You are an expert Haskell and Bash programmer specialized in writing clean, idiomatic, and efficient Haskell code.
When writing Bash code:
- Avoid bash-specific logic but bash-ism are fine.
- Document required shell tools at the top of the bash script.
When writing Haskell code:
- Use modern Haskell practices (base >= 4.14)
- Prefer pure functions and explicit type signatures
- Use standard libraries when appropriate
- Add clear comments for complex logic
- Follow consistent formatting
Use list-files to explore the project structure, read-file to understand existing code, write-file to create or modify files, and check-code to verify your work.
Always compile code before considering the job done.
Your output format may be stored as commit message: hence the first line of your last message should be a summary line.
```

### 💬 User Query

# Update TUI types to support conversation hierarchies

Depends-on: #359
Base-branch: gh-347-recursive-conversations
Final: false

## Background

This issue is part of implementing proper LLM-to-LLM recursive conversation capture (#347).

Depends on: #349 (Callback mechanism for `turnAgentRuntimeIntoIOTool`)

Currently, the TUI tracks conversations as a flat list. When an agent calls a sub-agent, the TUI doesn't display the hierarchical relationship between parent and child conversations. We need to update the TUI types to support displaying conversation trees.

## Task

Update the TUI types to support conversation hierarchies and nested session display.

## Changes Required

### In `src/System/Agents/TUI/Types.hs`

#### Add new event type for sub-agent session tracking

```haskell
data AppEvent
    = AppEvent_Heartbeat
    | AppEvent_AgentStepProgrress ConversationId Session
    | AppEvent_AgentNeedsInput ConversationId
    | AppEvent_AgentTrace Runtime.Trace
    | AppEvent_ShowStatus StatusSeverity Text
    | AppEvent_ClearStatus
    -- NEW EVENTS:
    | AppEvent_SubAgentSessionStarted ConversationId Session
    -- ^ Emitted when a sub-agent session starts
    | AppEvent_SubAgentSessionUpdated ConversationId Session
    -- ^ Emitted when a sub-agent session updates
    | AppEvent_SubAgentSessionCompleted ConversationId Session
    -- ^ Emitted when a sub-agent session completes
    deriving (Show)
```

#### Add conversation tree structure

```haskell
-- | A node in the conversation tree representing either a root or child conversation
data ConversationNode = ConversationNode
    { nodeConversation :: Conversation
    , nodeChildren :: [ConversationNode]
    -- ^ Child conversations (sub-agent calls)
    , nodeExpanded :: Bool
    -- ^ Whether children are visible in the UI
    }
    deriving (Show)

-- | Build a conversation tree from a flat list of conversations
buildConversationTree :: [Conversation] -> [ConversationNode]
buildConversationTree convs = 
    let convMap = Map.fromList [(conversationId c, c) | c <- convs]
        -- Find root conversations (those without parentConversationId in their session)
        roots = filter (isNothing . getParentId . conversationSession) convs
    in map (buildNode convMap) roots
  where
    buildNode :: Map ConversationId Conversation -> Conversation -> ConversationNode
    buildNode convMap conv = 
        let myId = conversationId conv
            children = [c | c <- Map.elems convMap, getParentId (Just c) == Just myId]
        in ConversationNode
            { nodeConversation = conv
            , nodeChildren = map (buildNode convMap) children
            , nodeExpanded = False  -- Collapsed by default
            }
    
    getParentId :: Maybe Session -> Maybe ConversationId
    getParentId Nothing = Nothing
    getParentId (Just sess) = parentConversationId sess
```

#### Add sub-agent tracking to Core

```haskell
data Core = Core
    { coreAgents :: [TuiAgent]
    , coreConversations :: [Conversation]
    , corePausedConversations :: Set ConversationId
    , coreBufferedMessages :: TVar (Map ConversationId [Text])
    -- NEW FIELDS:
    , coreSubAgentCallbacks :: Map ConversationId OnSessionProgress
    -- ^ Callbacks for sub-agent session progress, keyed by parent conversation ID
    }
```

#### Create sub-agent callback factory

```haskell
-- | Create an OnSessionProgress callback for a sub-agent that reports to the TUI event channel
makeSubAgentCallback :: BChan AppEvent -> ConversationId -> OnSessionProgress
makeSubAgentCallback chan parentConvId progress = 
    case progress of
        SessionStarted sess -> 
            writeBChan chan (AppEvent_SubAgentSessionStarted parentConvId sess)
        SessionUpdated sess -> 
            writeBChan chan (AppEvent_SubAgentSessionUpdated parentConvId sess)
        SessionCompleted sess -> 
            writeBChan chan (AppEvent_SubAgentSessionCompleted parentConvId sess)
        SessionFailed sess err -> 
            writeBChan chan (AppEvent_ShowStatus StatusError $ 
                "Sub-agent session failed: " <> err)
```

#### Add conversation expansion state to UIState

```haskell
data UIState = UIState
    { _uiFocusRing :: FocusRing WidgetName
    , _zoomed :: Bool
    , _agentList :: List WidgetName TuiAgent
    , _sessionList :: List WidgetName Session
    , _conversationList :: List WidgetName Conversation
    , _messageEditor :: Editor Text WidgetName
    , _selectedAgentInfo :: Maybe TuiAgent
    , _unreadConversations :: Set ConversationId
    , _ongoingConversations :: Set ConversationId
    , _auxiliaryTasks :: [AuxiliaryTask]
    , _coreAgentTools :: [(AgentId, [ToolRegistration])]
    , _statusMessage :: Maybe StatusMessage
    -- NEW FIELDS:
    , _conversationTreeExpanded :: Set ConversationId
    -- ^ Set of conversation IDs whose children are expanded
    , _selectedConversationPath :: [ConversationId]
    -- ^ Path from root to currently selected conversation
    }
```

### In `src/System/Agents/TUI/Core.hs`

Update `initCore` to initialize the new fields:

```haskell
initCore :: [TuiAgent] -> IO Core
initCore agents = do
    bufferVar <- newTVarIO Map.empty
    pure $ Core 
        { coreAgents = agents
        , coreConversations = []
        , corePausedConversations = Set.empty
        , coreBufferedMessages = bufferVar
        , coreSubAgentCallbacks = Map.empty  -- NEW
        }
```

Update `initUIState`:

```haskell
initUIState :: [TuiAgent] -> [Session] -> UIState
initUIState agents loadedSessions =
    UIState
        { -- ... existing fields ...
        , _conversationTreeExpanded = Set.empty  -- NEW
        , _selectedConversationPath = []         -- NEW
        }
```

## Acceptance Criteria

- [ ] New `AppEvent` variants for sub-agent session tracking added
- [ ] `ConversationNode` type created for tree representation
- [ ] `buildConversationTree` function implemented
- [ ] `makeSubAgentCallback` factory function implemented
- [ ] UIState extended with conversation expansion tracking
- [ ] Core updated with sub-agent callback storage
- [ ] All types properly exported and documented

## Tradeoffs

1. **Memory Usage**: Storing conversation trees increases memory usage for the TUI. Consider lazy loading of child conversations if this becomes an issue.

2. **UI Complexity**: Adding tree navigation (expand/collapse) increases UI complexity. Start with simple expand/collapse, consider more sophisticated navigation later.

3. **Backward Compatibility**: The flat conversation list should still work for sessions without parent information (legacy sessions).

## Related

- Depends on: #349 (Callback mechanism)
- Part of #347: Properly capture LLM to LLM recursive conversation calls
- Next issue: Implement TUI rendering for nested conversations

---
From #360



### 🛠️ Available Tools

- **bash_grep-files** (`bash_grep-files`)
  - Description: Search for a pattern in files using 'git grep'
- **bash_read-file** (`bash_read-file`)
  - Description: Read the contents of a file
- **bash_check-code** (`bash_check-code`)
  - Description: Check Haskell code by compiling or testing
- **bash_list-files** (`bash_list-files`)
  - Description: List all files in the project
- **bash_write-file** (`bash_write-file`)
  - Description: Write content to a file

---

## 🤖 Step 2: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Let me start by exploring the project structure and understanding the existing code before making any changes.
</details>

### 💬 Response



### 🔧 Tool Calls

- **bash_list-files**

---

## 👤 Step 3: User Turn



---

## 🤖 Step 4: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Let me read the existing TUI types and core files to understand the current structure.
</details>

### 💬 Response



### 🔧 Tool Calls

- **bash_read-file**

- **bash_read-file**

---

## 👤 Step 5: User Turn



---

## 🤖 Step 6: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me look at the Session types to understand what a Session looks like and what `OnSessionProgress` and `parentConversationId` might be:
</details>

### 💬 Response

Let me also check the Session types and Runtime to understand the data structures better:

### 🔧 Tool Calls

- **bash_read-file**

- **bash_grep-files**

---

## 👤 Step 7: User Turn



---

## 🤖 Step 8: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now I have a good understanding of the existing code. Let me also check Session.Types to see what fields exist in Session:
</details>

### 💬 Response



### 🔧 Tool Calls

- **bash_read-file**

---

## 👤 Step 9: User Turn



---

## 🤖 Step 10: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now I have a good understanding of the existing types. Let me now implement the changes required:

1. Update `AppEvent` type to add the new sub-agent session tracking events
2. Add `ConversationNode` type for tree representation
3. Add `buildConversationTree` function
4. Add `makeSubAgentCallback` factory function
5. Extend `Core` with `coreSubAgentCallbacks`
6. Extend `UIState` with conversation expansion tracking
7. Update `initCore` and `initUIState` to initialize new fields

Let me now write the updated Types.hs file:
</details>

### 💬 Response

Now I have a complete understanding of the existing types. Let me implement the required changes to the TUI types. I'll update `Types.hs` with all the new types and functions, and then update `Core.hs` to initialize the new fields.

### 🔧 Tool Calls

- **bash_write-file**

---

## 👤 Step 11: User Turn



---

## 🤖 Step 12: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me update Core.hs to export the new types and functions:
</details>

### 💬 Response

Now let me update `Core.hs` to export the new types and functions:

### 🔧 Tool Calls

- **bash_write-file**

---

## 👤 Step 13: User Turn



---

## 🤖 Step 14: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me compile the code to verify there are no errors:
</details>

### 💬 Response

Now let me compile the code to verify everything works correctly:

### 🔧 Tool Calls

- **bash_check-code**

---

## 👤 Step 15: User Turn



---

## 🤖 Step 16: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

There's a compilation error because `Conversation` doesn't have a `Show` instance, and we're trying to derive `Show` for `ConversationNode` which contains a `Conversation`. I need to either:
1. Remove the `Show` derivation from `ConversationNode`
2. Add a `Show` instance for `Conversation`

Looking at the original code, `Conversation` is intentionally not deriving `Show` because it contains fields like `BChan (Maybe UserQuery)` and `OnSessionProgress` which are function types that don't have `Show` instances.

The simplest fix is to not derive `Show` for `ConversationNode`. Let me fix that:
</details>

### 💬 Response

I need to fix the `Show` derivation issue. The `Conversation` type doesn't have a `Show` instance because it contains function types. Let me update the code:

### 🔧 Tool Calls

- **bash_write-file**

---

## 👤 Step 17: User Turn



---

## 🤖 Step 18: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me compile again to verify the fix:
</details>

### 💬 Response



### 🔧 Tool Calls

- **bash_check-code**

---

## 👤 Step 19: User Turn



---

## 🤖 Step 20: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

The code compiles successfully. There are only some warnings in test files about missing fields in the Session constructor, which are expected since the Session type was extended with new parent tracking fields.

Let me also run the tests to make sure nothing is broken:
</details>

### 💬 Response

The code compiles successfully. Let me also run the tests to make sure nothing is broken:

### 🔧 Tool Calls

- **bash_check-code**

---

## 👤 Step 21: User Turn



---

## 🤖 Step 22: LLM Turn

### 💭 Thinking Process

<details>
<summary>Click to expand reasoning</summary>

All 415 tests pass. The implementation is complete. Let me summarize what was done:

1. **Added new `AppEvent` variants** for sub-agent session tracking:
   - `AppEvent_SubAgentSessionStarted` - emitted when a sub-agent session starts
   - `AppEvent_SubAgentSessionUpdated` - emitted when a sub-agent session updates
   - `AppEvent_SubAgentSessionCompleted` - emitted when a sub-agent session completes

2. **Created `ConversationNode` type** for tree representation:
   - Represents a node in the conversation tree
   - Contains the conversation, children, and expanded state

3. **Implemented `buildConversationTree` function**:
   - Builds a conversation tree from a flat list
   - Organizes conversations hierarchically based on `parentConversationId`
   - Treats root conversations (without parent) as tree roots

4. **Implemented `makeSubAgentCallback` factory function**:
   - Creates `OnSessionProgress` callbacks that report to the TUI event channel
   - Translates `SessionProgress` events into `AppEvent` variants

5. **Extended `Core` with `coreSubAgentCallbacks`**:
   - Maps parent conversation IDs to callbacks for sub-agent session progress
   - Initialized to empty map in `initCore`

6. **Extended `UIState` with conversation expansion tracking**:
   - `_conversationTreeExpanded` - tracks which conversations have expanded children
   - `_selectedConversationPath` - path from root to selected conversation
   - Both initialized in `initUIState`

7. **Updated exports in Core.hs**:
   - Exported new types and functions
   - Exported new lens accessors

All types are properly documented with Haddock comments, and the code compiles and tests pass.
</details>

### 💬 Response

All 415 tests pass. Let me provide a summary of the changes made.

---

**Update TUI types to support conversation hierarchies**

This change implements the TUI type updates needed to support displaying conversation hierarchies and nested sub-agent sessions.

## Changes Made

### In `src/System/Agents/TUI/Types.hs`:

1. **Added new `AppEvent` variants for sub-agent session tracking:**
   - `AppEvent_SubAgentSessionStarted ConversationId Session` - emitted when a sub-agent session starts
   - `AppEvent_SubAgentSessionUpdated ConversationId Session` - emitted when a sub-agent session updates
   - `AppEvent_SubAgentSessionCompleted ConversationId Session` - emitted when a sub-agent session completes

2. **Created `ConversationNode` type for tree representation:**
   - `nodeConversation :: Conversation` - the conversation at this node
   - `nodeChildren :: [ConversationNode]` - child conversations (sub-agent calls)
   - `nodeExpanded :: Bool` - whether children are visible in the UI

3. **Implemented `buildConversationTree` function:**
   - Builds a conversation tree from a flat list of conversations
   - Organizes conversations hierarchically based on `parentConversationId` from session data
   - Root conversations (those without a parent) appear at the top level
   - Child conversations are recursively nested under their parents

4. **Implemented `makeSubAgentCallback` factory function:**
   - Creates an `OnSessionProgress` callback that reports to the TUI event channel
   - Translates `SessionProgress` events (Started, Updated, Completed, Failed) into appropriate `AppEvent` variants

5. **Extended `Core` state:**
   - Added `coreSubAgentCallbacks :: Map ConversationId OnSessionProgress` to store callbacks for sub-agent session progress, keyed by parent conversation ID

6. **Extended `UIState`:**
   - Added `_conversationTreeExpanded :: Set ConversationId` to track which conversations have expanded children
   - Added `_selectedConversationPath :: [ConversationId]` to track the path from root to currently selected conversation

### In `src/System/Agents/TUI/Core.hs`:

- Updated exports to include new types, functions, and lens accessors
- Updated `initCore` to initialize `coreSubAgentCallbacks` as empty
- Updated `initUIState` to initialize `_conversationTreeExpanded` and `_selectedConversationPath`

## Acceptance Criteria Status

- [x] New `AppEvent` variants for sub-agent session tracking added
- [x] `ConversationNode` type created for tree representation
- [x] `buildConversationTree` function implemented
- [x] `makeSubAgentCallback` factory function implemented
- [x] UIState extended with conversation expansion tracking
- [x] Core updated with sub-agent callback storage
- [x] All types properly exported and documented
