Claude Code Uses 4.7x More Tokens Than OpenCode Before You Type a Word

A benchmark by Systima found that Claude Code sends approximately 33,000 tokens of system prompts, tool schemas, and scaffolding per session before any user input, compared to roughly 7,000 tokens for OpenCode under identical test conditions. The study used a logging proxy to capture exact API request payloads, with both tools pointed at the same model and run in clean, empty environments. Claude Code also re-wrote up to 54 times more prompt-cache tokens per session than OpenCode, and since cache writes are billed at a premium, costs can climb significantly. However, the benchmark noted one advantage for Claude Code: on multi-step tasks, it batches tool calls into fewer requests, which can result in a lower total token count compared to OpenCode's turn-by-turn approach. The researchers emphasize that session structure — not just baseline overhead — ultimately determines which tool costs more in real-world use.