Rebuild the docs around tested examples; shrink README.v2.md to a pitch (#2978)

docs_src/elicitation/tutorial001.py

@@ -0,0 +1,26 @@
+from pydantic import BaseModel, Field
+
+from mcp.server import MCPServer
+from mcp.server.mcpserver import Context
+
+mcp = MCPServer("Bistro")
+
+
+class AlternativeDate(BaseModel):
+    accept_alternative: bool = Field(description="Try another date?")
+    date: str = Field(default="2025-12-26", description="Alternative date (YYYY-MM-DD)")
+
+
+@mcp.tool()
+async def book_table(date: str, party_size: int, ctx: Context) -> str:
+    """Book a table at the bistro."""
+    if date != "2025-12-25":
+        return f"Booked a table for {party_size} on {date}."
+
+    result = await ctx.elicit(
+        message=f"No tables for {party_size} on {date}. Would you like to try another date?",
+        schema=AlternativeDate,
+    )
+    if result.action == "accept" and result.data.accept_alternative:
+        return await book_table(result.data.date, party_size, ctx)
+    return "No booking made."