UserPromptSubmit

UserPromptSubmit is a hook for Claude Code from hashgraph-online/hol-cigar. Its token cost is not measured, scanned A, a copy of SessionStart, Apache-2.0.

A prompt-submission hook that runs a shell command after you submit a prompt and before the agent receives it.

In plain words
What is it for?
Running the CIGAR check on every submitted prompt.
Why use it?
It allows an automatic check or processing step to happen before the agent handles your request.

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 cigar plugin — 5 skills, 3 agents, 18 hooks, 1 MCP server shipped together

One of 18 entries in hooks.json — they are configured in one file and arrive together.

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 hashgraph-online/hol-cigar
Claude Code
/plugin install cigar

Made for: Claude Code.

Or install cigar, the plugin that ships this one along with the rest of its 5 skills, 3 agents, 18 hooks, 1 MCP server.

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/hashgraph-online/hol-cigar/user-prompt-submit.svg)](https://agentmods.dev/hooks/hashgraph-online/hol-cigar/user-prompt-submit)
Your own site
<a href="https://agentmods.dev/hooks/hashgraph-online/hol-cigar/user-prompt-submit"><img src="https://agentmods.dev/badge/hooks/hashgraph-online/hol-cigar/user-prompt-submit.svg" alt="Measured on agentmods" 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. Scan, not verified.
Origin 91% 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 5d 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

91% identical to SessionStart — 2 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.

adapters/claude-code/hooks/hooks.json · 20 lines

What it actually says

{
  "UserPromptSubmit": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "${CLAUDE_PLUGIN_ROOT}/bin/cigar-claude-hook",
          "args": [
            "run",
            "--plugin-root",
            "${CLAUDE_PLUGIN_ROOT}",
            "--plugin-data",
            "${CLAUDE_PLUGIN_DATA}"
          ],
          "timeout": 1
        }
      ]
    }
  ]
}
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. 5d ago First seen · 20 lines scan A 0c70f66885b4

Subscribe to this mod's changes

UserPromptSubmit is a hook published in the GitHub repository hashgraph-online/hol-cigar (8 stars, last pushed 2d ago), licensed Apache-2.0. 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. It is 91% identical to SessionStart, differing in 2 lines, and is treated as a copy.