PostToolUse

A set of automatic actions that run after edits, file writes, and selected Git commands finish. It formats and checks Python files, updates context files, and applies other checks described in the configuration.

In plain words
What is it for?
It helps maintain Python source and test files, refresh project context, and run checks after commits, pulls, checkouts, and merges.
Why use it?
It removes the need to remember routine formatting, linting, and context-update commands after common coding actions.

Hook for Claude Code

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/vishnu2kmohan/mcp-server-langgraph/post-tool-use
Clone the repo
git clone --depth 1 https://github.com/vishnu2kmohan/mcp-server-langgraph

Made for: Claude Code.

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

PostToolUse 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 yesterday.

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.

.claude/settings.json · 94 lines

How it starts

The opening of the file, as written. The whole thing — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.

{
  "PostToolUse": [
    {
      "matcher": "Edit(**src/**)",
      "hooks": [
        {
          "type": "command",
          "command": "echo '⚙️  Auto-formatting and linting...' && uv run ruff format --diff --quiet {{file_path}} 2>/dev/null && uv run ruff check --fix --quiet {{file_path}} 2>/dev/null || true",
          "timeout": 10
        }
      ]
    },
    {
      "matcher": "Write(**src/**)",
      "hooks": [
        {
          "type": "command",
          "command": "echo '⚙️  Auto-formatting and linting...' && uv run ruff format --diff --quiet {{file_path}} 2>/dev/null && uv run ruff check --fix --quiet {{file_path}} 2>/dev/null || true",
          "timeout": 10
        }
      ]
    },
    {
      "matcher": "Edit(**tests/**)",
      "hooks": [
        {
          "type": "command",
          "command": "echo '⚙️  Auto-formatting test code...' && uv run ruff format --diff --quiet {{file_path}} 2>/dev/null && uv run ruff check --fix --quiet {{file_path}} 2>/dev/null || true",
          "timeout": 10
        },
        {
          "type": "command",
          "command": "if grep -q 'AsyncMock\\|MagicMock' {{file_path}} 2>/dev/null; then echo '⚠️  Memory Safety: AsyncMock/MagicMock detected. Ensure class has @pytest.mark.xdist_group and teardown_method with gc.collect()'; fi",
          "timeout": 5
        }
      ]
    },
    {
      "matcher": "Write(**tests/**)",
      "hooks": [
        {
          "type": "command",
          "command": "echo '⚙️  Auto-formatting test code...' && uv run ruff format --diff --quiet {{file_path}} 2>/dev/null && uv run ruff check --fix --quiet {{file_path}} 2>/dev/null || true",
          "timeout": 10
        },
        {
          "type": "command",
          "command": "if grep -q 'AsyncMock\\|MagicMock' {{file_path}} 2>/dev/null; then echo '⚠️  Memory Safety: AsyncMock/MagicMock detected. Ensure class has @pytest.mark.xdist_group and teardown_method with gc.collect()'; fi",
          "timeout": 5
        }
      ]

Read the full file on GitHub · 94 lines

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. yesterday First seen · 94 lines scan A da48bd9d2b4c

Subscribe to this mod's changes

PostToolUse is a hook published in the GitHub repository vishnu2kmohan/mcp-server-langgraph (4 stars, last pushed 8d 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 2026-08-31.