agentmods.dev

UserPromptSubmit

An automatic hook that runs when you submit a prompt, before the agent reads it. It starts a Node.js script that checks whether stored memory may be relevant.

In plain words
What is it for?
Use it to perform a quick memory-relevance check on every submitted prompt.
Why use it?
It can surface useful saved context without requiring you to run a separate command each time.

Hook

Part of the memwal plugin — 1 skill, 7 commands, 3 hooks, 1 MCP server shipped together

0 14d ago A scan tokens not measured original Apache-2.0
View the source file CommandOSSLabs/walrus-memory-mcp-plugin
Install

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.

agentmods
npx agentmods add hooks/commandosslabs/walrus-memory-mcp-plugin/user-prompt-submit
Clone the repo
git clone --depth 1 https://github.com/CommandOSSLabs/walrus-memory-mcp-plugin

Or install memwal, the plugin that ships this one along with the rest of its 1 skill, 7 commands, 3 hooks, 1 MCP server.

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 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 2d 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": [
    {
      "hooks": [
        {
          "type": "command",
          "command": "node \"${CLAUDE_PLUGIN_ROOT}/scripts/on_user_prompt.mjs\"",
          "statusMessage": "Checking memory relevance...",
          "timeout": 8
        }
      ]
    }
  ]
}
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. 2d ago First seen · 14 lines scan A 7dca92dbb768

Subscribe to this mod's changes

UserPromptSubmit is a hook published in the GitHub repository CommandOSSLabs/walrus-memory-mcp-plugin (0 stars, last pushed 14d 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. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Memory and contextclaude-codemcpsuiwalrus
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