CSV State File Format

State files are stored at ~/.claude/statusline/statusline.<session_id>.state. Each line is a CSV record with 15 comma-separated fields.

Field Specification

Index	Field	Type	Description
0	timestamp	integer	Unix timestamp in seconds
1	total_input_tokens	integer	Cumulative input tokens for the session
2	total_output_tokens	integer	Cumulative output tokens for the session
3	current_input_tokens	integer	Input tokens for the current request
4	current_output_tokens	integer	Output tokens for the current request
5	cache_creation	integer	Cache creation input tokens
6	cache_read	integer	Cache read input tokens
7	cost_usd	float	Total session cost in USD
8	lines_added	integer	Total lines added in session
9	lines_removed	integer	Total lines removed in session
10	session_id	string	Session identifier (UUID)
11	model_id	string	Model identifier (e.g., claude-opus-4-5)
12	workspace_project_dir	string	Project directory path (commas replaced with underscores)
13	context_window_size	integer	Context window size in tokens
14	api_duration_ms	integer	Cumulative API wait time in milliseconds (cost.total_api_duration_ms); powers the tok/s throughput display

Constraints

• Fields are separated by commas with no quoting or escaping.
• The workspace_project_dir field (index 12) is sanitized before writing: all comma characters (,) are replaced with underscores (_) to prevent CSV corruption.
• Numeric fields default to 0 when absent. String fields default to empty string.
• Lines are newline-terminated (\n).
• Files are append-only.
• Files are automatically rotated at 10,000 lines (keeps most recent 5,000) by the Python statusline script.
• Duplicate entries (same token count as previous line) are skipped to prevent file bloat.

Legacy Format

Older state files may contain 2-field lines: timestamp,total_input_tokens. The reader defaults all other fields to zero/empty for these lines.

State files written before the api_duration_ms field was added contain 14 fields (through context_window_size). The reader defaults api_duration_ms to 0 for these lines, and field access is length-guarded so both 14- and 15-field rows parse correctly. Conversely, older readers ignore the extra trailing field, so the change is backward-compatible in both directions.

Example

1710288000,75000,8500,50000,5000,10000,20000,0.05234,250,45,abc-123-def,claude-opus-4-5,/home/user/my-project,200000,5000