Module diff 

Unified-diff rendering for file-modifying tools.

Produces a compact, user-facing unified diff (with +N -M stats and a line cap) so channel adapters and the web UI can show exactly what an edit_file / write_file call changed, instead of a bare success line.

Structs

UnifiedDiff

A rendered unified diff plus its summary stats.

Constants

DEFAULT_DIFF_MAX_LINES

Default cap on rendered diff lines (matching the 120-line convention popularized by Grok Build’s diff view).

FILE_DIFF_METADATA_KEY

Key under which file-modifying tools attach their diff payload to ToolResult::metadata. Shared so the producer (tools) and consumers (tool executor → AgentEvent::FileDiff) cannot silently desync.

Functions

file_diff_metadata

Build the metadata payload for a file edit diff.

format_diff_chat_message

Format a chat-facing message for a file diff: a one-line header with the path and +N -M stats, followed by a fenced ```diff block.

unified_diff

Compute a unified diff between old and new, capped at max_lines rendered lines. Returns None when the contents are identical.