feat: claude-sdk-python adds hitl-in-chat, declarative-gen-ui, a2ui-fixed-schema, gen-ui-tool-based manifest

- hitl-in-chat (+ booking alias): frontend useHumanInTheLoop book_call tool;
  basic Claude SDK chat agent forwards AG-UI tool defs and lets standard
  tool-call lifecycle resolve the user's choice.
- declarative-gen-ui: backend a2ui_dynamic agent owns generate_a2ui tool
  (calls secondary OpenAI client bound to render_a2ui), dedicated runtime
  route with injectA2UITool: false.
- a2ui-fixed-schema: backend a2ui_fixed ships flight_schema.json and the
  display_flight tool emitting a2ui_operations directly; dedicated runtime
  route with injectA2UITool: false.
- gen-ui-tool-based: manifest entry for the existing haiku demo
  (useFrontendTool + useRenderTool).
- Per-demo READMEs documenting the architectural choice for each cell.

Author: AlemTuzlak

showcase/integrations/claude-sdk-python/manifest.yaml

@@ -17,6 +17,7 @@ generative_ui:
   - constrained-explicit
   - a2ui-fixed-schema
   - a2ui-dynamic-schema
+  - declarative-schema
 interaction_modalities:
   - sidebar
   - embedded
@@ -55,6 +56,11 @@ features:
   - tool-rendering-reasoning-chain
   - mcp-apps
   - beautiful-chat
+  - gen-ui-tool-based
+  - hitl-in-chat
+  - hitl-in-chat-booking
+  - declarative-gen-ui
+  - a2ui-fixed-schema
 not_supported_features:
   - gen-ui-interrupt
   - interrupt-headless
@@ -426,3 +432,65 @@ demos:
     highlight:
       - src/app/demos/beautiful-chat/page.tsx
       - src/app/api/copilotkit/route.ts
+  - id: gen-ui-tool-based
+    name: Tool-Based Generative UI
+    description: Agent uses tools to trigger UI generation (haiku generator via useFrontendTool + useRenderTool)
+    tags:
+      - generative-ui
+    route: /demos/gen-ui-tool-based
+    animated_preview_url:
+    highlight:
+      - src/agents/agent.py
+      - src/app/demos/gen-ui-tool-based/page.tsx
+      - src/app/api/copilotkit/route.ts
+  - id: hitl-in-chat
+    name: In-Chat HITL (useHumanInTheLoop — ergonomic API)
+    description: Interactive approval/decision surface rendered inline in the chat via the high-level `useHumanInTheLoop` hook
+    tags:
+      - interactivity
+    route: /demos/hitl-in-chat
+    animated_preview_url:
+    highlight:
+      - src/agents/hitl_in_chat_agent.py
+      - src/app/demos/hitl-in-chat/page.tsx
+      - src/app/demos/hitl-in-chat/time-picker-card.tsx
+      - src/app/api/copilotkit/route.ts
+  - id: hitl-in-chat-booking
+    name: In-Chat HITL (Booking)
+    description: Time-picker card rendered inline via useHumanInTheLoop for a booking flow
+    tags:
+      - interactivity
+    route: /demos/hitl-in-chat
+    animated_preview_url:
+    highlight:
+      - src/agents/hitl_in_chat_agent.py
+      - src/app/demos/hitl-in-chat/page.tsx
+      - src/app/demos/hitl-in-chat/time-picker-card.tsx
+      - src/app/api/copilotkit/route.ts
+  - id: declarative-gen-ui
+    name: Declarative Generative UI (A2UI)
+    description: Canonical A2UI BYOC — custom catalog (Card/StatusBadge/Metric/InfoRow/PrimaryButton/PieChart/BarChart) wired via a2ui.catalog on the provider; backend agent owns the `generate_a2ui` tool with injectA2UITool false
+    tags:
+      - generative-ui
+    route: /demos/declarative-gen-ui
+    animated_preview_url:
+    highlight:
+      - src/agents/a2ui_dynamic.py
+      - src/app/demos/declarative-gen-ui/page.tsx
+      - src/app/demos/declarative-gen-ui/a2ui/catalog.ts
+      - src/app/demos/declarative-gen-ui/a2ui/definitions.ts
+      - src/app/demos/declarative-gen-ui/a2ui/renderers.tsx
+      - src/app/api/copilotkit-declarative-gen-ui/route.ts
+  - id: a2ui-fixed-schema
+    name: Declarative Generative UI (A2UI — Fixed Schema)
+    description: A2UI rendering against a known client-side schema; the backend ships flight_schema.json and only streams data via display_flight
+    tags:
+      - generative-ui
+    route: /demos/a2ui-fixed-schema
+    animated_preview_url:
+    highlight:
+      - src/agents/a2ui_fixed.py
+      - src/agents/a2ui_schemas/flight_schema.json
+      - src/app/demos/a2ui-fixed-schema/page.tsx
+      - src/app/demos/a2ui-fixed-schema/a2ui/catalog.ts
+      - src/app/api/copilotkit-a2ui-fixed-schema/route.ts

showcase/integrations/claude-sdk-python/src/agent_server.py

@@ -44,10 +44,13 @@
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.responses import StreamingResponse
 
+from agents.a2ui_dynamic import run_a2ui_dynamic_agent
+from agents.a2ui_fixed import run_a2ui_fixed_agent
 from agents.agent import create_app, run_agent
 from agents.agent_config_agent import build_system_prompt, read_properties
 from agents.byoc_hashbrown_agent import BYOC_HASHBROWN_SYSTEM_PROMPT
 from agents.byoc_json_render_agent import BYOC_JSON_RENDER_SYSTEM_PROMPT
+from agents.hitl_in_chat_agent import run_hitl_in_chat_agent
 from agents.mcp_apps_agent import run_mcp_apps_agent
 from agents.multimodal_agent import SYSTEM_PROMPT as MULTIMODAL_SYSTEM_PROMPT
 from agents.multimodal_agent import convert_part_for_claude
@@ -283,6 +286,66 @@ async def event_stream() -> AsyncIterator[str]:
     )
 
 
+@app.post("/hitl-in-chat")
+async def hitl_in_chat_endpoint(request: Request) -> StreamingResponse:
+    """In-Chat HITL demo — frontend `book_call` tool via `useHumanInTheLoop`."""
+    body = await request.json()
+    input_data = RunAgentInput(**body)
+
+    async def event_stream() -> AsyncIterator[str]:
+        async for chunk in run_hitl_in_chat_agent(input_data):
+            yield chunk
+
+    return StreamingResponse(
+        event_stream(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "X-Accel-Buffering": "no",
+        },
+    )
+
+
+@app.post("/declarative-gen-ui")
+async def declarative_gen_ui_endpoint(request: Request) -> StreamingResponse:
+    """Declarative Generative UI (A2UI Dynamic Schema) demo."""
+    body = await request.json()
+    input_data = RunAgentInput(**body)
+
+    async def event_stream() -> AsyncIterator[str]:
+        async for chunk in run_a2ui_dynamic_agent(input_data):
+            yield chunk
+
+    return StreamingResponse(
+        event_stream(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "X-Accel-Buffering": "no",
+        },
+    )
+
+
+@app.post("/a2ui-fixed-schema")
+async def a2ui_fixed_schema_endpoint(request: Request) -> StreamingResponse:
+    """A2UI Fixed Schema demo — backend ships flight_schema.json."""
+    body = await request.json()
+    input_data = RunAgentInput(**body)
+
+    async def event_stream() -> AsyncIterator[str]:
+        async for chunk in run_a2ui_fixed_agent(input_data):
+            yield chunk
+
+    return StreamingResponse(
+        event_stream(),
+        media_type="text/event-stream",
+        headers={
+            "Cache-Control": "no-cache",
+            "X-Accel-Buffering": "no",
+        },
+    )
+
+
 def main() -> None:
     """Run the uvicorn server."""
     port = int(os.getenv("AGENT_PORT", "8000"))