fnox is a secret manager that stores credentials either encrypted in a Git repository or in supported cloud and password-management services. Developers use it to provide secrets to commands and shell sessions across development, continuous integration, and production. The catalogue includes instructions for using fnox.
Borrowing it
Nothing to install: this file belongs to jdx/fnox. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/jdx/fnox/main/.claude/settings.jsongit clone --depth 1 https://github.com/jdx/fnoxWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/hooks/jdx/fnox/post-tool-use-failure)<a href="https://agentmods.dev/hooks/jdx/fnox/post-tool-use-failure"><img src="https://agentmods.dev/badge/hooks/jdx/fnox/post-tool-use-failure/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/hooks/jdx/fnox/post-tool-use-failure"><img src="https://agentmods.dev/badge/hooks/jdx/fnox/post-tool-use-failure.svg" alt="Reviewed on agentmods" width="80" height="20"></a>Grade A, and why
PostToolUseFailure scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the commands this hook runs, not an audit. A hook is shell that executes on your machine at the event it names, which is why every command in it is printed with what was found.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
{
"PostToolUseFailure": [
{
"matcher": "Bash",
"hooks": [
{
"type": "command",
"command": "sh -c 'command -v jouet >/dev/null 2>&1 || exit 0; exec jouet hook claude post-tool-use-failure'",
"timeout": 10
}
]
}
]
}What else settings.json configures
This page is one entry in a file that holds 10. Installing the file brings all of them; each is measured and scanned on its own page.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- yesterday First seen · 14 lines scan A 1759c503ddb9
PostToolUseFailure is a hook published in the GitHub repository jdx/fnox (2,355 stars, last pushed today), licensed MIT. Its token cost is not measured: a hook is shell that never enters the context. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-11-03.
Other hooks, from other repositories
SessionStart
Runs when a session starts on startup, executing install_pkgs.sh. From supabase/supabase.
PostToolUse
Runs after a tool call finishes for Write and Edit tool calls, executing format_and_lint.sh. From supabase/supabase.
SessionStart
Runs when a session starts, executing on-start.js via node. From google-gemini/gemini-cli.
PreToolUse
Runs before the agent uses a tool for Bash tool calls, running an inline shell check. From apache/superset.
PreToolUse
Runs before the agent uses a tool, executing pre-write.sh and pre-bash.sh (2 commands). From anthropics/claude-cookbooks.
PostToolUse
Runs after a tool call finishes for Bash tool calls, executing hooks.sh via sh (3 commands). From anthropics/claude-plugins-official.