Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add hooks/twowells/catenary/post-tool-use-failuregit clone --depth 1 https://github.com/TwoWells/CatenaryWrote 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/twowells/catenary/post-tool-use-failure)<a href="https://agentmods.dev/hooks/twowells/catenary/post-tool-use-failure"><img src="https://agentmods.dev/badge/hooks/twowells/catenary/post-tool-use-failure.svg" alt="Measured on agentmods" 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 3d ago.
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.
The source is not reproduced here
Licensed AGPL-3.0
The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
What else hooks.json configures
This page is one entry in a file that holds 27. Installing the file brings all of them; each is measured and scanned on its own page.
- Hook ConfigChange A not measured
- Hook CwdChanged A not measured
- Hook Elicitation A not measured
- Hook ElicitationResult A not measured
- Hook InstructionsLoaded A not measured
- Hook Notification A not measured
- Hook PermissionDenied A not measured
- Hook PermissionRequest A not measured
- Hook PostCompact A not measured
- Hook PostToolUse A not measured
- Hook PreCompact A not measured
- Hook PreToolUse A not measured
- Hook SessionEnd A not measured
- Hook SessionStart C not measured
- Hook Setup A not measured
- Hook Stop A not measured
- Hook StopFailure A not measured
- Hook SubagentStart A not measured
- Hook SubagentStop A not measured
- Hook TaskCompleted A not measured
- Hook TaskCreated A not measured
- Hook TeammateIdle A not measured
- Hook UserPromptExpansion A not measured
- Hook UserPromptSubmit A not measured
- Hook WorktreeCreate A not measured
- Hook WorktreeRemove A not measured
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.
- 3d ago First seen · 13 lines scan A 06096efa244f
PostToolUseFailure is a hook published in the GitHub repository TwoWells/Catenary (8 stars, last pushed 28d ago), licensed AGPL-3.0. 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 2026-08-31.
Other hooks, from other repositories
Stop
Runs when the agent finishes a response, running concord inbox drain --format stop. From Get-Concord-AI/concord-mcp.
PreToolUse
Runs before the agent uses a tool for Bash, Edit, Write, MultiEdit and NotebookEdit tool calls, executing block-npm-publish.sh, block-unsafe-git.sh and block-generated-edit.sh (3 commands). From wlsdks/ontology-atlas.
Stop
Runs when the agent finishes a response, executing check-completion.sh via bash with --quiet. From andr-ca/agentharness.
UserPromptSubmit
Runs when you submit a prompt, before the agent sees it, executing _run_hook.sh via bash. From lemoncrow-lab/lemoncrow.
PostToolUse
Runs after a tool call finishes for Write and Edit tool calls, executing post-write-archcodex.sh. From ArchCodexOrg/archcodex.
SessionStart
Runs when a session starts, running agent-recall-session-start. From mnardit/agent-recall.