docs: add UI simplification spec for BYOK cleanup

Addresses GitHub issues #52 and #53:
- Remove api_provider dropdown (auto-detect from key prefix)
- Simplify examples table to just query + mode
- Clearer free tier messaging

Spec: docs/bugs/FIX_UI_SIMPLIFICATION.md

docs/bugs/FIX_UI_SIMPLIFICATION.md

@@ -0,0 +1,201 @@
+# UI Simplification: Remove Anthropic Provider
+
+**Issues**: #52, #53
+**Priority**: P1 - UX improvement for hackathon demo
+**Estimated Time**: 30 minutes
+
+---
+
+## Problem
+
+The current UI has confusing BYOK (Bring Your Own Key) settings:
+
+1. **Provider dropdown is misleading** - Shows "openai" but actually uses free tier when no key
+2. **Examples table shows useless columns** - API Key (empty), Provider (ignored)
+3. **Anthropic doesn't work with Advanced mode** - Only OpenAI has `agent-framework` support
+
+## Solution
+
+Remove `api_provider` dropdown entirely. Auto-detect provider from key prefix.
+
+---
+
+## Implementation
+
+### File: `src/app.py`
+
+#### 1. Update `configure_orchestrator()` signature
+
+```python
+# BEFORE
+def configure_orchestrator(
+    use_mock: bool = False,
+    mode: str = "simple",
+    user_api_key: str | None = None,
+    api_provider: str = "openai",  # REMOVE THIS
+) -> tuple[Any, str]:
+
+# AFTER
+def configure_orchestrator(
+    use_mock: bool = False,
+    mode: str = "simple",
+    user_api_key: str | None = None,
+) -> tuple[Any, str]:
+```
+
+#### 2. Auto-detect provider from key prefix
+
+```python
+# Inside configure_orchestrator, replace provider logic with:
+if user_api_key:
+    # Auto-detect provider from key prefix
+    if user_api_key.startswith("sk-ant-"):
+        # Anthropic key
+        anthropic_provider = AnthropicProvider(api_key=user_api_key)
+        model = AnthropicModel(settings.anthropic_model, provider=anthropic_provider)
+        backend_info = "Paid API (Anthropic)"
+    elif user_api_key.startswith("sk-"):
+        # OpenAI key
+        openai_provider = OpenAIProvider(api_key=user_api_key)
+        model = OpenAIModel(settings.openai_model, provider=openai_provider)
+        backend_info = "Paid API (OpenAI)"
+    else:
+        raise ValueError("Invalid API key format. Expected sk-... (OpenAI) or sk-ant-... (Anthropic)")
+
+    judge_handler = JudgeHandler(model=model)
+```
+
+#### 3. Update `research_agent()` signature
+
+```python
+# BEFORE
+async def research_agent(
+    message: str,
+    history: list[dict[str, Any]],
+    mode: str = "simple",
+    api_key: str = "",
+    api_provider: str = "openai",  # REMOVE THIS
+) -> AsyncGenerator[str, None]:
+
+# AFTER
+async def research_agent(
+    message: str,
+    history: list[dict[str, Any]],
+    mode: str = "simple",
+    api_key: str = "",
+) -> AsyncGenerator[str, None]:
+```
+
+#### 4. Update warning message for Advanced mode
+
+```python
+# BEFORE
+if mode == "advanced" and not (has_openai or (has_user_key and api_provider == "openai")):
+
+# AFTER
+is_openai_key = user_api_key and user_api_key.startswith("sk-") and not user_api_key.startswith("sk-ant-")
+if mode == "advanced" and not (has_openai or is_openai_key):
+    yield (
+        "⚠️ **Advanced mode requires OpenAI API key.** "
+        "Anthropic keys only work in Simple mode. Falling back to Simple.\\n\\n"
+    )
+    mode = "simple"
+```
+
+#### 5. Simplify examples (remove provider column)
+
+```python
+# BEFORE
+examples=[
+    ["What drugs improve female libido post-menopause?", "simple", "", "openai"],
+    ["Clinical trials for erectile dysfunction alternatives to PDE...", "simple", "", "openai"],
+    ["Evidence for testosterone therapy in women with HSDD?", "simple", "", "openai"],
+]
+
+# AFTER
+examples=[
+    ["What drugs improve female libido post-menopause?", "simple", ""],
+    ["Clinical trials for ED alternatives to PDE5 inhibitors?", "simple", ""],
+    ["Evidence for testosterone therapy in women with HSDD?", "simple", ""],
+]
+```
+
+#### 6. Remove provider from additional_inputs
+
+```python
+# BEFORE
+additional_inputs=[
+    gr.Radio(
+        choices=["simple", "advanced"],
+        value="simple",
+        label="Orchestrator Mode",
+        ...
+    ),
+    gr.Textbox(
+        label="🔑 API Key (Optional - BYOK)",
+        ...
+    ),
+    gr.Radio(  # REMOVE THIS ENTIRE BLOCK
+        choices=["openai", "anthropic"],
+        value="openai",
+        label="API Provider",
+        ...
+    ),
+]
+
+# AFTER
+additional_inputs=[
+    gr.Radio(
+        choices=["simple", "advanced"],
+        value="simple",
+        label="Orchestrator Mode",
+        info="Simple: Works with free tier | Advanced: Requires OpenAI key",
+    ),
+    gr.Textbox(
+        label="🔑 API Key (Optional)",
+        placeholder="sk-... (OpenAI) or sk-ant-... (Anthropic)",
+        type="password",
+        info="Leave empty for free tier (Llama 3.1). Auto-detects provider from key.",
+    ),
+]
+```
+
+#### 7. Update accordion label
+
+```python
+additional_inputs_accordion=gr.Accordion(
+    label="⚙️ Settings (Free tier works without API key)",
+    open=False
+),
+```
+
+---
+
+## Testing
+
+### Manual Tests
+1. **No key**: Should use free tier (HuggingFace Inference)
+2. **OpenAI key**: Should detect and use OpenAI
+3. **Anthropic key**: Should detect and use Anthropic in Simple mode
+4. **Anthropic key + Advanced**: Should warn and fallback to Simple
+
+### Unit Test Updates
+- Update `tests/unit/test_app_smoke.py` if it checks additional_inputs count
+
+---
+
+## Definition of Done
+
+- [ ] `api_provider` parameter removed from both functions
+- [ ] Auto-detection logic works for both key types
+- [ ] Examples table only shows 2 columns (query, mode)
+- [ ] Accordion label updated
+- [ ] Placeholder text shows key formats
+- [ ] Advanced mode warning works with auto-detection
+- [ ] All existing tests pass
+
+---
+
+## Related
+- Issue #52: UI Polish - Examples table confusion
+- Issue #53: API Provider Simplification