UserPromptSubmit

UserPromptSubmit is a hook for Claude Code from letta-ai/claude-subconscious. Its token cost is not measured, scanned A, original, MIT.

A hook that runs a Node.js memory-synchronization script whenever you submit a prompt. It runs before the coding agent receives the prompt.

In plain words
What is it for?
Use it in projects that need prompt-time memory synchronization before the agent starts handling each user request.
Why use it?
It keeps stored session information synchronized automatically instead of relying on a separate manual step for each 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 claude-subconscious plugin — 4 hooks shipped together

One of 4 entries in hooks.json upstream. Installing this one merges just its entry into your config; the other 3 are separate, each on its own page.

Good fit Use it in projects that need prompt-time memory synchronization before the agent starts handling each user request.

Compare 6 hooks from other repositories ↓
About the project

Claude Subconscious is a demonstration application that runs a background agent alongside Claude Code, reading session transcripts and project files to build memory and provide guidance. It is intended for experimenting with persistent, behind-the-scenes assistance in coding sessions rather than production use. Its catalogue add-ons extend the Claude Code workflow with hooks and a plugin.

letta-ai/claude-subconscious · 2,888 stars · on GitHub · docs.letta.com

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 letta-ai/claude-subconscious
Claude Code
/plugin install claude-subconscious

Made for: Claude Code.

Or install claude-subconscious, the plugin that ships this one along with the rest of its 4 hooks.

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/letta-ai/claude-subconscious/user-prompt-submit/github.svg)](https://agentmods.dev/hooks/letta-ai/claude-subconscious/user-prompt-submit)
Your own site
<a href="https://agentmods.dev/hooks/letta-ai/claude-subconscious/user-prompt-submit"><img src="https://agentmods.dev/badge/hooks/letta-ai/claude-subconscious/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/letta-ai/claude-subconscious/user-prompt-submit"><img src="https://agentmods.dev/badge/hooks/letta-ai/claude-subconscious/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 original No closer match found 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 10d 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.

hooks/hooks.json · 14 lines

What it actually says

{
  "UserPromptSubmit": [
    {
      "matcher": "*",
      "hooks": [
        {
          "type": "command",
          "command": "node \"${CLAUDE_PLUGIN_ROOT:-.}/hooks/silent-npx.cjs\" tsx \"${CLAUDE_PLUGIN_ROOT:-.}/scripts/sync_letta_memory.ts\"",
          "timeout": 10
        }
      ]
    }
  ]
}
Same file

What else hooks.json configures

This page is one entry in a file that holds 4. 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. 10d ago First seen · 14 lines scan A 5f159ada44ae

Subscribe to this mod's changes

UserPromptSubmit is a hook published in the GitHub repository letta-ai/claude-subconscious (2,888 stars, last pushed 13d 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. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.