Normalize fd redirects in command safety check#208
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The `>` redirect detection in isSafeCommand() was falsely blocking common curl patterns like `curl ... 2>/dev/null` and `curl ... 2>&1 | head`. This prevented agents from fetching web content (e.g. via jina.ai or markdown.new) during planning mode. Fix: strip safe fd redirects (2>/dev/null, 2>&1, &>/dev/null) from the command before checking against destructive patterns, while still blocking actual file redirects like `> output.txt`. https://claude.ai/code/session_01Jk1P5aZPERSzrmA9urfb4B
The planning phase system prompt says "bash (read-only commands only)" which causes models to self-censor and not attempt curl/wget for web content fetching (e.g. jina.ai, markdown.new). Update the prompt to explicitly mention curl/wget is allowed, and mention web fetching in the explore step instructions. https://claude.ai/code/session_01Jk1P5aZPERSzrmA9urfb4B
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Summary
Updated the
isSafeCommandfunction to normalize file descriptor redirects before checking against destructive patterns. This prevents legitimate commands with safe output redirections from being incorrectly flagged as unsafe.Key Changes
N>/dev/null- redirects any file descriptor to /dev/nullN>&M- file descriptor merges (e.g.,2>&1)&>/dev/null- bash shorthand for redirecting all output to /dev/nullImplementation Details
The fix addresses a false positive issue where commands like
curl ... 2>/dev/nullorcurl ... 2>&1 | headwould be incorrectly blocked by the>destructive pattern rule. By removing these safe redirections before pattern matching, we allow legitimate commands while maintaining security checks for actual destructive operations.https://claude.ai/code/session_01Jk1P5aZPERSzrmA9urfb4B