PR #20066: fix(terminal): prevent safety filter false positives on keywords inside quoted strings

• Repository: NousResearch/hermes-agent
• Author: kshitijk4poor
• State: open | merged: False
• Link: https://github.com/NousResearch/hermes-agent/pull/20066

Description (problem / solution / changelog)

Problem

The terminal tool's safety filter blocks legitimate commands when keywords like nohup, disown, or setsid appear inside quoted strings — e.g., in commit messages, Python -c code, gh pr create --body text, or grep patterns.

Examples that get incorrectly blocked:

python3 -c "x = 'preexec_fn=os.setsid'"
git commit -m "fix: replace preexec_fn=os.setsid with process_group=0"
gh pr create --body "We removed os.setsid..."
grep -r 'nohup' tests/

Root Cause

_foreground_background_guidance() in tools/terminal_tool.py uses:

_SHELL_LEVEL_BACKGROUND_RE = re.compile(r"\b(?:nohup|disown|setsid)\b", re.IGNORECASE)

This matches the keyword anywhere in the full command text, including inside quoted strings.

Fix

Two-layer approach:

1. _strip_quotes() helper — Removes single-quoted, double-quoted, and backtick-quoted content before pattern matching, so keywords inside strings are invisible to the regexes.

2. Position-aware regex — Tightened to only match keywords at shell command positions (after ^, ;, &&, ||, $() rather than at any word boundary.

Both layers are needed: quote stripping handles the common case (keywords in string literals), and the position-aware regex handles unquoted edge cases.

Testing

• All 14 test_terminal_tool.py tests pass
• All 45 test_terminal_compound_background.py + test_terminal_foreground_timeout_cap.py tests pass
• Verified 7 false-positive cases now pass (quoted keywords)
• Verified 5 true-positive cases still blocked (actual background wrapper usage)

Fixes #20064

Changed files

• tools/terminal_tool.py (modified, +28/-4)

PR #20079: fix(terminal): prevent safety filter false positives on keywords inside quoted strings

• Repository: NousResearch/hermes-agent
• Author: JasonOA888
• State: closed | merged: False
• Link: https://github.com/NousResearch/hermes-agent/pull/20079

Description (problem / solution / changelog)

Summary

The background-wrapper detection regex (nohup/disown/setsid) matched keywords anywhere in the command text, including inside quoted strings. This blocked legitimate commands:

git commit -m "fix: replace preexec_fn=os.setsid with process_group=0"
grep -r 'nohup' tests/
python3 -c "x = 'preexec_fn=os.setsid'"
gh pr create --body "We removed os.setsid..."

Fix

Added _strip_quoted_content() which removes content inside single/double/backtick quotes before the regex match. Only keywords in the actual shell structure trigger the safety filter.

Testing

• All 14 test_terminal_tool.py tests pass
• All 45 compound_background + foreground_timeout_cap tests pass
• 4 false-positive cases now correctly pass through
• 4 true-positive cases still correctly blocked

Closes #20064 Closes #20066

Changed files

• tools/terminal_tool.py (modified, +40/-1)

PR #20099: fix: reduce false positives in terminal safety filter for nohup/disown/setsid

• Repository: NousResearch/hermes-agent
• Author: vominh1919
• State: open | merged: False
• Link: https://github.com/NousResearch/hermes-agent/pull/20099

Description (problem / solution / changelog)

What

Fix the terminal tool's safety filter regex to only match nohup/disown/setsid when they are used as actual shell commands, not when they appear inside quoted strings, commit messages, or code.

Fixes #20064

The Bug

The _SHELL_LEVEL_BACKGROUND_RE regex uses a naive \b(?:nohup|disown|setsid)\b pattern that matches these keywords anywhere in the command string. This causes false positives that block legitimate commands:

# All of these get incorrectly blocked:
git commit -m "fix: replace setsid with process_group"
python3 -c "x = 'preexec_fn=os.setsid'"
echo "The function os.setsid() creates a new session"
gh pr create --body "We removed setsid from the code"
grep -r setsid .

Users hit this frequently when:

• Writing commit messages about process management
• Reviewing PRs that mention these functions
• Running Python/Ruby code that references os.setsid()
• Using echo/grep to search for these terms

Fix

Replace the naive regex with one that only matches when the keyword appears at the start of a command or after shell operators (;, |, &&, ||, subshell ():

# Before (matches anywhere in string):
_SHELL_LEVEL_BACKGROUND_RE = re.compile(r"\b(?:nohup|disown|setsid)\b", re.IGNORECASE)

# After (matches only as actual commands):
_SHELL_LEVEL_BACKGROUND_RE = re.compile(
    r"(?:^|[;&|]\s*|&&\s*|\|\|\s*|\(\s*)(?:nohup|disown|setsid)\b",
    re.IGNORECASE | re.MULTILINE,
)

Before vs After

Tests

Added 5 new tests to tests/tools/test_terminal_foreground_timeout_cap.py:

• test_foreground_allows_setsid_mentioned_in_string — commit message
• test_foreground_allows_setsid_in_python_code — Python code string
• test_foreground_allows_setsid_in_echo — echo text
• test_foreground_rejects_setsid_after_semicolon — actual ; chaining
• test_foreground_rejects_setsid_after_pipe — actual pipe usage

All 16 tests pass (11 existing + 5 new).

Changed files

• tests/tools/test_terminal_foreground_timeout_cap.py (modified, +88/-0)
• tools/terminal_tool.py (modified, +4/-1)

PR #20101: fix(terminal): strip quoted strings before safety-filter regex scan (#20064)

• Repository: NousResearch/hermes-agent
• Author: Bartok9
• State: closed | merged: False
• Link: https://github.com/NousResearch/hermes-agent/pull/20101

Description (problem / solution / changelog)

Summary

Fixes #20064

The _foreground_background_guidance function used a naive word-boundary regex to detect shell-level background wrappers (nohup/disown/setsid). This caused false positives whenever these keywords appeared inside quoted arguments — commit messages, Python -c strings, PR body text, grep patterns, etc.:

# All of these were incorrectly blocked:
git commit -m "fix: replace preexec_fn=os.setsid with process_group=0"
python3 -c "x = 'preexec_fn=os.setsid'"
gh pr create --body "We removed the nohup call"
echo 'The nohup command prevents SIGHUP from killing the process'
grep -r 'disown' ./docs/

Root Cause

_SHELL_LEVEL_BACKGROUND_RE scanned the entire command string including quoted content, so any occurrence of the keywords triggered the filter regardless of context.

Fix

Add a _strip_quoted_strings() helper that removes single- and double-quoted string literals (honouring backslash escapes) before the safety-filter regexes are applied. All three pattern checks (_SHELL_LEVEL_BACKGROUND_RE, _INLINE_BACKGROUND_AMP_RE, _TRAILING_BACKGROUND_AMP_RE, and _LONG_LIVED_FOREGROUND_PATTERNS) now operate on the unquoted shell structure.

# NEW: strip quoted content first
unquoted = _strip_quoted_strings(command)
if _SHELL_LEVEL_BACKGROUND_RE.search(unquoted):   # ← was: search(command)
    ...

Verified

• All 6 false-positive cases above now pass through correctly (no error)
• All true-positive cases (bare nohup/setsid/disown, & backgrounding, long-lived server patterns) still fire correctly
• All 11 existing test_terminal_foreground_timeout_cap.py tests continue to pass
• 20 new regression tests added in tests/tools/test_terminal_safety_filter_false_positives.py

Changed files

• agent/auxiliary_client.py (modified, +46/-10)
• run_agent.py (modified, +8/-5)
• tests/run_agent/test_compression_feasibility.py (modified, +65/-0)
• tests/tools/test_terminal_safety_filter_false_positives.py (added, +151/-0)
• tools/terminal_tool.py (modified, +26/-3)

PR #20146: fix(terminal): stop false-positive on quoted nohup/disown/setsid (#20064)

• Repository: NousResearch/hermes-agent
• Author: Sanjays2402
• State: open | merged: False
• Link: https://github.com/NousResearch/hermes-agent/pull/20146

Description (problem / solution / changelog)

Closes #20064.

The terminal tool's _foreground_background_guidance() regex was matching nohup/disown/setsid anywhere in the command string, including inside quoted strings, Python -c code, commit messages, and PR bodies. Legit commands like git commit -m "replace preexec_fn=os.setsid with process_group=0" got blocked with a request to use terminal(background=true).

Fix

Two-layer match:

1. Strip single/double-quoted spans before matching, so quoted occurrences don't fire the filter.
2. Boundary-anchored regex — only matches at start of command, after ;, |, &&, ||, newline, or open-paren. So even unquoted text like xargs setsid foo doesn't accidentally re-fire.

The issue suggested either approach; this PR uses both because each catches cases the other misses.

Verified

• All 4 false-positive cases from the issue body now pass the filter.
• Genuine setsid foo, nohup ./script.sh &, cmd && nohup foo, (setsid foo), multi-line, and mixed-case still get redirected to background=true.
• 35 new pinned cases in tests/tools/test_terminal_quoted_background_wrapper_filter.py.
• Pre-existing terminal tests (114 tests across test_terminal_tool.py, test_terminal_compound_background.py, test_terminal_requirements.py, test_terminal_foreground_timeout_cap.py) still pass.

Notes

• Quote-stripping doesn't special-case ANSI-C $'...' or heredocs; the boundary regex handles those by requiring a command-position prefix, keeping false-positive risk low. Documented in the helper docstring.
• No CHANGELOG.md exists in this repo — release notes are auto-generated from conventional commits, so the fix(terminal): prefix is enough.

Changed files

• tests/tools/test_terminal_quoted_background_wrapper_filter.py (added, +174/-0)
• tools/terminal_tool.py (modified, +56/-2)