                 Changes in version 0.1.0 (2026-08-03)                  

  - First release of the lightweight, tools-only Model Context Protocol
    (MCP) server over standard input and output (stdio), supporting the
    MCP lifecycle, ping, tools/list, and tools/call.
  - Supports protocol versions 2024-11-05, 2025-06-18, and 2025-11-25.
  - Provides native tool and JSON Schema helpers, with optional
    interoperability for compatible ellmer tool definitions.
  - Adds explicit protocol-native tool results through tool_result() and
    the content_text(), content_image(), content_audio(),
    content_resource_link(), and content_resource() constructors.
    Results may contain ordered mixed content, structured content,
    annotations, and metadata while ordinary R return values retain
    their existing text conversion.
  - Adds object-shaped output_schema support to tool(). Tool definitions
    and results follow the negotiated MCP version: structured output,
    output schemas, audio, resource links, and content metadata are
    available for 2025-06-18 and later, with compatible fallback or
    contained tool errors for 2024-11-05.
  - Handles protocol negotiation, request validation, JSON-RPC errors,
    and MCP tool-call errors while keeping the stdio protocol stream
    usable.
  - Automatically traces every envelope-valid MCP operation with one
    OpenTelemetry server span, while keeping tool-authored child spans
    optional. Standard otel and otelsdk configuration owns provider and
    exporter selection, remote W3C parent context is accepted through
    params._meta, and request or tool content is not captured by
    default. Stdio servers must use a stderr or remote exporter because
    stdout is reserved for MCP messages; with no exporter configured,
    tracing is an effective no-op.
