Release 0.6.0

Added

• Example modules: examples/ with 5 runnable demo modules — 3 class-based (text_echo, math_calc, greeting) and 2 binding.yaml (convert_temperature, word_count) — for quick Explorer UI demo out of the box.

Changed

• BREAKING: ExecutionRouter.handle_call() return type: Changed from (content, is_error) to (content, is_error, trace_id). Callers that unpack the 2-tuple must update to 3-tuple unpacking.
• BREAKING: Explorer /call response format: Changed from {"result": ...} / {"error": ...} to MCP-compliant CallToolResult format: {"content": [...], "isError": bool, "_meta": {"_trace_id": ...}}.

Fixed

• MCP protocol compliance: Router no longer injects _trace_id as a content block in tool results. trace_id is now returned as a separate tuple element and surfaced in Explorer responses via _meta. Factory handler raises exceptions for errors so the MCP SDK correctly sets isError=True.
• Explorer UI default values: defaultFromSchema() now correctly skips null defaults and falls through to type-based placeholders, fixing blank form fields for binding.yaml modules.