Generate a human-readable text representation of an LLM trace event. This endpoint converts AI observability events ($ai_generation, $ai_span, $ai_embedding, or $ai_trace) into formatted text representations suitable for display, logging, or analysis. **Supported Event Types:** - `$ai_generation`: Individual LLM API calls with input/output messages - `$ai_span`: Logical spans with state transitions - `$ai_embedding`: Embedding generation events (text input → vector) - `$ai_trace`: Full traces with hierarchical structure **Options:** - `max_length`: Maximum character count (default: 2000000) - `truncated`: Enable middle-content truncation within events (default: true) - `truncate_buffer`: Characters at start/end when truncating (default: 1000) - `include_markers`: Use interactive markers vs plain text indicators (default: true) - Frontend: set true for `<<<TRUNCATED|base64|...>>>` markers - Backend/LLM: set false for `... (X chars truncated) ...` text - `collapsed`: Show summary vs full trace tree (default: false) - `include_hierarchy`: Include tree structure for traces (default: true) - `max_depth`: Maximum depth for hierarchical rendering (default: unlimited) - `tools_collapse_threshold`: Number of tools before auto-collapsing list (default: 5) - Tool lists >5 items show `<<<TOOLS_EXPANDABLE|...>>>` marker for frontend - Or `[+] AVAILABLE TOOLS: N` for backend when `include_markers: false` - `include_line_numbers`: Prefix each line with line number like L001:, L010: (default: false) **Use Cases:** - Frontend display: `truncated: true, include_markers: true, include_line_numbers: true` - Backend LLM context (summary): `truncated: true, include_markers: false, collapsed: true` - Backend LLM context (full): `truncated: false` The response includes the formatted text and metadata about the rendering.