cost-tracking

Cost Tracking

Use this skill to analyze Claude Code cost and usage history from a local SQLite database. It is intended for users who already have a cost-tracking hook or plugin writing usage rows to ~/.claude-cost-tracker/usage.db.

Source: salvaged from stale community PR #1304 by MayurBhavsar.

When to Use

• The user asks "how much have I spent?", "what did this session cost?", or "what is my token usage?"
• The user mentions budgets, spending limits, overruns, or cost controls.
• The user wants a cost breakdown by project, tool, session, model, or date.
• The user wants to compare today against yesterday or inspect a recent trend.
• The user asks for a CSV export of recent usage records.

How It Works

First verify prerequisites:

command -v sqlite3 >/dev/null && echo "sqlite3 available" || echo "sqlite3 missing"
test -f ~/.claude-cost-tracker/usage.db && echo "Database found" || echo "Database not found"

If the database is missing, do not fabricate usage data. Tell the user that cost tracking is not configured and suggest installing or enabling a trusted local cost-tracking hook/plugin.

The expected usage table usually contains one row per tool call or model interaction. Column names vary by tracker, but the examples below assume:

Column	Meaning
timestamp	ISO timestamp for the usage event
project	Project or repository name
tool_name	Tool or event name
input_tokens	Input token count, when recorded
output_tokens	Output token count, when recorded
cost_usd	Precomputed cost in USD
session_id	Claude Code session identifier
model	Model used for the event

Prefer cost_usd over hand-calculating pricing. Model prices and cache pricing change over time, and the tracker should be the source of truth for how each row was priced.

Examples

Quick Summary

sqlite3 ~/.claude-cost-tracker/usage.db "
  SELECT
    'Today: $' || ROUND(COALESCE(SUM(CASE WHEN date(timestamp) = date('now') THEN cost_usd END), 0), 4) ||
    ' | Total: $' || ROUND(COALESCE(SUM(cost_usd), 0), 4) ||
    ' | Calls: ' || COUNT(*) ||
    ' | Sessions: ' || COUNT(DISTINCT session_id)
  FROM usage;
"