Fix chat responses failing due to null deserialization and tool call errors

[Copilot]

Chat feature returns null when Ollama API responses fail to deserialize or when AI tool calls (web search, URL reading) fail or return empty responses, leaving users with "No response received".

Changes

• Added null check after deserialization: Added validation to check if the deserialized response is null before accessing its properties, preventing NullReferenceException that was causing chat failures
• Changed control flow in ChatAsync(): Replaced else if with if on line 448 to enable fallback to original response content when tool execution fails
• Enhanced error logging: Added debug statements to log deserialization failures and missing content scenarios for better diagnostics

Technical Detail

Critical Fix: Null Deserialization Check

// Before: crashed when result was null
var result = JsonConvert.DeserializeObject<OllamaChatResponse>(responseContent);
LastPromptTokens = result.PromptEvalCount;  // NullReferenceException if result is null

// After: validates result before accessing properties
var result = JsonConvert.DeserializeObject<OllamaChatResponse>(responseContent);
if (result == null) {
    System.Diagnostics.Debug.WriteLine("Ollama chat error: Failed to deserialize response");
    return null;
}
LastPromptTokens = result.PromptEvalCount;  // Safe to access

Tool Call Fallback Fix

// Before: tool call failures fell through to return null
if (result?.Message?.ToolCalls != null && result.Message.ToolCalls.Count > 0) {
    // ... execute tools, make follow-up request ...
    // If follow-up fails, falls through
}
else if (result?.Message?.Content != null) {  // Never reached after tool calls
    return CleanResponse(result.Message.Content);
}

// After: fallback executes regardless of tool call path
if (result?.Message?.ToolCalls != null && result.Message.ToolCalls.Count > 0) {
    // ... execute tools, make follow-up request ...
    // If follow-up fails, continues to fallback
}
if (result?.Message?.Content != null) {  // Now executes as fallback
    return CleanResponse(result.Message.Content);
}

The chat feature now properly handles both deserialization failures and tool call errors, ensuring users receive responses whenever valid content is available from the Ollama API.

Original prompt

The chat feature isn't recieving responses anymore.

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[ExtCan]

@copilot Still no response recieved

[Copilot]

@copilot Still no response recieved

Found the issue - the code was throwing a NullReferenceException when deserializing the API response. Added null check before accessing response properties in commit 288d4d5.

The original fix only addressed tool call fallbacks, but the actual bug was earlier: if JSON deserialization failed or returned null, the code would crash when trying to access result.PromptEvalCount without checking if result was null first.

Also added debug logging to help diagnose if there are still issues. Please try again and check the log file (MSAgentAI.log) if you still see problems.

[ExtCan]

@copilot Your logging system sucks. Also, it still doesn't work.

[02:24:11] === MSAgent AI Log Started ===
[02:24:11] Date: 2025-12-27 02:24:11
[02:24:11] OS: Microsoft Windows NT 6.2.9200.0
[02:24:11] .NET Runtime: 4.0.30319.42000
[02:24:11] 64-bit Process: False
[02:24:11] ================================
[02:24:11] Application starting...
[02:24:11] Initializing MS Agent...
[02:24:11] Trying to create agent server with ProgID: AgentServer.Agent
[02:24:11] ProgID AgentServer.Agent not found
[02:24:11] Trying to create agent server with ProgID: Agent.Control.2
[02:24:11] Set Connected = true for Agent.Control.2
[02:24:11] Successfully initialized MS Agent using ProgID: Agent.Control.2
[02:24:11] Initializing SAPI4 voice engine...
[02:24:11] SAPI4 voice engine initialized successfully
[02:24:11] Setting voice to: TTS_MS_EN-GB_HAZEL_11.0
[02:24:11] Enumerating SAPI4 TTS Modes...
[02:24:11] Found SAPI4 TTS Mode: Microsoft Hazel Desktop - English (Great Britain) (ModeID: TTS_MS_EN-GB_HAZEL_11.0)
[02:24:11] Found SAPI4 TTS Mode: Microsoft Zira Desktop - English (United States) (ModeID: TTS_MS_EN-US_ZIRA_11.0)
[02:24:11] Found SAPI5 voice: Microsoft George - English (United Kingdom)
[02:24:11] Found SAPI5 voice: Microsoft Hazel - English (United Kingdom)
[02:24:11] Found SAPI5 voice: Microsoft Susan - English (United Kingdom)
[02:24:11] Found 5 SAPI4 TTS modes
[02:24:11] Voice ModeID set to: TTS_MS_EN-GB_HAZEL_11.0
[02:24:12] Pipeline TCP server started on 127.0.0.1:8765
[02:24:12] Communication pipeline initialized
[02:24:12] Loading character from: C:\Windows\msagent\chars\MaxALERT.acs
[02:24:12] Character name: MaxALERT
[02:24:12] Trying Method 1: Characters.Load via dynamic binding
[02:24:12] Got Characters collection
[02:24:12] TCP Pipeline: Listening on 127.0.0.1:8765
[02:24:12] Called Characters.Load(MaxALERT, C:\Windows\msagent\chars\MaxALERT.acs)
[02:24:12] Got character object from collection
[02:24:12] SUCCESS: Character 'MaxALERT' loaded successfully
[02:24:12] [ERROR] Failed to set TTSModeID to TTS_MS_EN-GB_HAZEL_11.0
Exception: COMException - An unknown application-defined or object-defined failure occurred.
[02:24:12] Setting speech speed to: 150
[02:24:12] [ERROR] Failed to set character Speed property
Exception: TargetParameterCountException - Error while invoking Speed.
[02:24:12] Setting speech pitch to: 100
[02:24:12] [ERROR] Failed to set character Pitch property
Exception: TargetParameterCountException - Error while invoking Pitch.
[02:24:12] Set speech volume to: 65535
[02:24:12] [ERROR] Failed to set TTSModeID to TTS_MS_EN-GB_HAZEL_11.0
Exception: COMException - An unknown application-defined or object-defined failure occurred.
[02:24:12] Applied voice settings: Speed=150, Pitch=100, Voice=TTS_MS_EN-GB_HAZEL_11.0

[ExtCan]

@copilot Revert to comit before the websearching merge

[Copilot]

@copilot Revert to comit before the websearching merge

I need clarification - the web search functionality (EnableWebSearch, EnableUrlReading, tool calls) was already in the codebase before my changes.

Do you want me to:

1. Revert all 4 of my commits (288d4d5, ed28a99, d18333c, 43b601a) and go back to commit 48a5d02?
2. Or are you referring to an earlier merge in the main branch history that I don't have access to?

Please clarify which commit hash you want me to revert to, or if you want me to disable the web search/tool call features while keeping my other fixes.

[ExtCan]

@copilot go back to 48a5d02