Every harness runs shell commands. What differs underneath?

Not surveyed yet. No implementation of this capability has been read from source, so there is no comparison to show — only the list of what is on file, below. The dimensions worth comparing are decided by reading the implementations, not before.

Present but not verified. 24 tools, registered by 13 harnesses, have not been read from source: Claude Code Bash, Claude Code BashOutput, Codex exec_command, Codex unified_exec, Codex write_stdin, dsh bash-persistent, dsh bash, dsh pwsh, dsh terminal_open/read/send, Grok Build bash, Grok Build monitor, Hermes process, Hermes terminal, Kimi Code bash, MiMo Code bash-interactive, MiMo Code bash, OpenClaw exec, OpenClaw process, OpenClaw terminal, opencode bash, OpenHands terminal, pi bash, Qwen Code run_shell_command, ZCode Bash.