Expand agent participant configuration with logging, debugging, and web search

[jeromewynne-jpg]

Hiya! I found agent participants weren't completing stages as intended and had their responses incorrectly parsed in group chats so have vibe-coded a fix. Code was written by Claude - I did my best to guide it towards making the minimum changes necessary and not introduce any breaking changes.

As part of the PR I've included a way to view agent participant API logs in the UI and have expanded the agent participant config UI component. Here's a video showing the result:

Summary

This PR enhances agent participant functionality with three main improvements:

1. Agent Log Viewer - New section in participant stats page to view agent model call history
2. Bug Fixes - Debugged and fixed several issues preventing agent participants from working correctly
3. Expanded Configuration - New dialog for quick-adding agents with model selection, web search, and chat settings

Changes

Agent Log Viewer

• Added "Agent log" section to participant stats page
• Displays model call history with prompts, responses, and timestamps
• Helps debug agent behavior and track API interactions

Agent Participant Bug Fixes

• Fixed chat settings not being applied for quick-add agents (settings were not merged into prompt config)
• Fixed Claude API not capturing responses when web search is enabled (text was in last content block, not first)
• Fixed OpenAI structured output compatibility issues
• Fixed empty response handling for Gemini API
• Added debug logging for troubleshooting agent behavior

Expanded Agent Configuration

• New agent-participant-configuration-dialog component
• Support for multiple LLM providers: Gemini, OpenAI, Claude, and Ollama
• Web search capability for Gemini (Google Search grounding) and Claude (web_search tool)
• Chat settings: typing speed, min messages before responding, self-triggering, max responses
• Fixed dialog z-index to appear above cohort-list header

Backend Changes

• Added useWebSearch to AgentModelSettings interface
• Gemini API: Google Search grounding via googleSearch tool
• Claude API: web_search_20250305 tool integration
• Fixed Claude API text extraction for multi-block responses

Testing

I've created a few experiments with 'group chat', 'set your profile', and 'survey' stages, and have tested them against each combination of (Google/Anthropic/OpenAI, w/wo web search), with between one and four agent participants. The parsing errors have disappeared, the API log viewer seems to work, and the new agent participant settings worked as intended.

I haven't included automated tests as the contrib guidelines didn't ask for them, however if you have something in mind please say.

• View agent logs in participant stats page
• Add agent participant via cohort panel dialog
• Test with Gemini model (with and without web search)
• Test with Claude model (with and without web search)
• Verify web search option is hidden for OpenAI and Ollama
• Verify chat settings are applied correctly

Known Limitations

• OpenAI web search not supported - the code's using the Chat Completions API rather than the Responses API, ideally it would use the Responses API
• Ollama web search not supported

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[jeromewynne-jpg]

I'd signed it but needed to resync, if you check now you should you should see I've signed

[jeromewynne-jpg]

I see that the CLA check is failing for Claude 😆

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