#10 High
The Token Furnace
Feeding entire codebases and node_modules to Claude
! $5,623 in a single month from one developer
Sending entire repositories, node_modules, or massive log files to Claude. 50-90% of tokens are wasted on irrelevant content. One developer hit $5,623 in a single month across 201 sessions. Another burned 10 billion tokens over 8 months.
DON'T
Feed everything to Claude
# Include the entire repo + node_modules "color:#7C5CFC">claude "color:#d97757">--add-dir ./node_modules \ -p "Find the bug in my app" # Or paste entire log files "color:#7C5CFC">cat production.log | "color:#7C5CFC">claude -p "What went wrong?" # production.log is 50,000 lines # 95% of those lines are irrelevant
DO
Targeted context, filtered input
# Use .claudeignore (like .gitignore) # .claudeignore node_modules/ dist/ *.log *.lock coverage/ # Filter before piping "color:#7C5CFC">tail -100 production.log | "color:#7C5CFC">grep ERROR | \ "color:#7C5CFC">claude -p "Diagnose these errors" # Point to specific files "color:#7C5CFC">claude -p "Fix the bug in src/auth.ts and src/middleware.ts. The error is: TypeError: Cannot read property role of null"
Sources
Community Cost Reports Anthropic Context Docs