UserPromptSubmit

UserPromptSubmit is a hook for Claude Code from ViryaZheng/promptly-prompt. Its token cost is not measured, scanned A, a copy of PreToolUse, MIT.

A hook that runs a Python script whenever you submit a prompt, before the coding agent receives it. It uses the intercept script from the promptly-prompt plugin.

In plain words
What is it for?
Use it to run prompt-interception logic on every submitted request through the plugin’s configured command.
Why use it?
It provides an automatic step for processing submitted prompts before the agent starts working on them.

Hook for Claude Code

Written for Claude Code: ${CLAUDE_PLUGIN_ROOT} variable.

Runs only inside its plugin — its command needs a path that Claude Code sets for a plugin’s own hooks and for nothing else. Install the plugin, not this.

Part of the promptly-prompt plugin — 1 skill, 1 hook shipped together

Good fit Use it to run prompt-interception logic on every submitted request through the plugin’s configured command.

Compare 6 hooks from other repositories ↓
Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code
/plugin marketplace add ViryaZheng/promptly-prompt
Claude Code
/plugin install promptly-prompt

Made for: Claude Code.

Or install promptly-prompt, the plugin that ships this one along with the rest of its 1 skill, 1 hook.

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 UserPromptSubmit

README.md
[![agentmods](https://agentmods.dev/badge/hooks/viryazheng/promptly-prompt/user-prompt-submit/github.svg)](https://agentmods.dev/hooks/viryazheng/promptly-prompt/user-prompt-submit)
Your own site
<a href="https://agentmods.dev/hooks/viryazheng/promptly-prompt/user-prompt-submit"><img src="https://agentmods.dev/badge/hooks/viryazheng/promptly-prompt/user-prompt-submit/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 UserPromptSubmit

Your own site · 80×15
<a href="https://agentmods.dev/hooks/viryazheng/promptly-prompt/user-prompt-submit"><img src="https://agentmods.dev/badge/hooks/viryazheng/promptly-prompt/user-prompt-submit.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 78% copy Near-identical to another mod in the catalogue.
Security

Grade A, and why

UserPromptSubmit 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

78% identical to PreToolUse — 27 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.

hooks/hooks.json · 13 lines

What it actually says

{
  "UserPromptSubmit": [
    {
      "matcher": "",
      "hooks": [
        {
          "type": "command",
          "command": "python3 \"${CLAUDE_PLUGIN_ROOT}/skill/scripts/intercept.py\""
        }
      ]
    }
  ]
}
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 First seen · 13 lines scan A 280c26b789d8

Subscribe to this mod's changes

UserPromptSubmit is a hook published in the GitHub repository ViryaZheng/promptly-prompt (37 stars, last pushed 2mo ago), 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 78% identical to PreToolUse, differing in 27 lines, and is treated as a copy.