ox: Hook for Claude Code

.claude/settings.json

SessionStart is a hook for Claude Code from sageox/ox. Its token cost is not measured, scanned A, a copy of PostToolUse, MIT.

A startup hook that runs two shell checks whenever a coding-agent session begins. It checks for the project's task and SageOx command-line tools, then loads context or shows an installation notice.

In plain words
What is it for?
Running startup checks, loading SageOx context, and telling users when the required command-line tools are missing.
Why use it?
It automatically prepares shared project context when the session starts. This reduces the chance that an agent begins work without the repository's team information or setup instructions.

Hook for Claude Code

Written for Claude Code: SessionStart hook event.

This is sageox/ox's own configuration. It tells Claude Code how to work on ox itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything ox configures →

One of 7 entries in settings.json upstream. Installing this one merges just its entry into your config; the other 6 are separate, each on its own page.

Reuse

Borrowing it

Nothing to install: this file belongs to sageox/ox. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/sageox/ox/main/.claude/settings.json
Clone the repo
git clone --depth 1 https://github.com/sageox/ox

Made for: Claude Code.

Wrote 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.

agentmods badge for SessionStart

README.md
[![agentmods](https://agentmods.dev/badge/hooks/sageox/ox/session-start/github.svg)](https://agentmods.dev/hooks/sageox/ox/session-start)
Your own site
<a href="https://agentmods.dev/hooks/sageox/ox/session-start"><img src="https://agentmods.dev/badge/hooks/sageox/ox/session-start/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.

agentmods 80×15 button for SessionStart

Your own site · 80×15
<a href="https://agentmods.dev/hooks/sageox/ox/session-start"><img src="https://agentmods.dev/badge/hooks/sageox/ox/session-start.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session not measured What this adds to a session before it is invoked.
When invoked not measured Not applicable: nothing here is loaded into a session.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 81% copy Near-identical to another mod in the catalogue.
Security

Grade A, and why

SessionStart 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 11d 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.

Origin

This is a copy

81% identical to PostToolUse — 8 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.claude/settings.json · 17 lines

How it starts

The opening of the file, as written. The whole thing — 17 lines — stays where its author put it; the contents beside it link to each section on GitHub.

{
  "SessionStart": [
    {
      "hooks": [
        {
          "command": "if command -v bd >/dev/null 2>&1; then bd prime 2>&1 || true; else echo '{\"sageox\": {\"notice\": \"This repo uses SageOx: install https://github.com/sageox/ox for optimized team context.\"}}'; fi",
          "type": "command"
        },
        {
          "command": "if command -v ox >/dev/null 2>&1; then AGENT_ENV=claude-code ox agent hook SessionStart 2>&1 || true; else _ox_p=\"\"; _ox_home=\"${HOME:-}\"; [ -n \"${GOBIN:-}\" ] && [ -x \"${GOBIN:-}/ox\" ] && _ox_p=\"${GOBIN:-}\"; [ -z \"$_ox_p\" ] && if command -v go >/dev/null 2>&1; then _ox_gb=\"$(go env GOBIN 2>/dev/null)\"; [ -n \"$_ox_gb\" ] && [ -x \"$_ox_gb/ox\" ] && _ox_p=\"$_ox_gb\"; if [ -z \"$_ox_p\" ]; then _ox_gp=\"$(go env GOPATH 2>/dev/null)/bin\"; [ -x \"$_ox_gp/ox\" ] && _ox_p=\"$_ox_gp\"; fi; fi; [ -n \"$_ox_home\" ] && [ -z \"$_ox_p\" ] && [ -x \"$_ox_home/go/bin/ox\" ] && _ox_p=\"$_ox_home/go/bin\"; [ -n \"$_ox_home\" ] && [ -z \"$_ox_p\" ] && [ -x \"$_ox_home/.local/bin/ox\" ] && _ox_p=\"$_ox_home/.local/bin\"; [ -z \"$_ox_p\" ] && [ -x \"/usr/local/bin/ox\" ] && _ox_p=\"/usr/local/bin\"; [ -z \"$_ox_p\" ] && [ -x \"/opt/homebrew/bin/ox\" ] && _ox_p=\"/opt/homebrew/bin\"; if [ -n \"$_ox_p\" ]; then printf '%s\\n' 'ox is installed at '\"$_ox_p\"'/ox but is not on PATH for non-interactive shells.'; _ox_sh=\"${SHELL:-}\"; _ox_e='s/[\\\\\"$`]/\\\\&/g'; if [ \"${_ox_sh##*/}\" = fish ]; then _ox_e='s/[\\\\\"$]/\\\\&/g'; fi; _ox_q=\"$(printf '%s' \"$_ox_p\" | sed \"$_ox_e\" 2>/dev/null)\" || _ox_q=\"\"; case \"${_ox_sh##*/}\" in zsh) echo 'AI coding tools run hooks in a non-interactive shell, which reads ~/.zshenv but not ~/.zshrc.'; echo 'Add this line to ~/.zshenv:'; if [ -n \"$_ox_q\" ]; then printf '%s\\n' '    export PATH=\"$PATH:'\"$_ox_q\"'\"'; fi;; bash) _ox_rc='~/.bashrc'; if [ \"$(uname -s 2>/dev/null)\" = Darwin ]; then _ox_rc='~/.bash_profile'; for _ox_f in .bash_profile .bash_login .profile; do if [ -n \"$_ox_

Read the full file on GitHub · 17 lines

Same file

What else settings.json configures

This page is one entry in a file that holds 7. Installing the file brings all of them; each is measured and scanned on its own page.

Changes

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.

  1. 11d ago Changed c15c7db0faf4
  2. 1mo ago Changed scan C → A fd0dfbfd9205
  3. 1mo ago Changed scan A → C 4cec9cded685
  4. 1mo ago First seen · 17 lines scan A 6319b50d8f52

Subscribe to this mod's changes

SessionStart is a hook published in the GitHub repository sageox/ox (64 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. It is 81% identical to PostToolUse, differing in 8 lines, and is treated as a copy.