---
published: true
id: post-tool-use
title: PostToolUse
description: Knowledge captured in João Lopes' learning graph.
tags:
- claude-code
- hooks
locale: en
resource: https://joaolopes.dev.br/knowledge/concepts/en/post-tool-use/
created: '2026-03-28'
---

# PostToolUse
A Claude Code hook event that fires after a tool call completes successfully, receiving the tool name, parameters, and result.

## Definition
PostToolUse hooks run after a tool has already executed. The hook can annotate the result with additional context (stdout is appended to what the model sees on the next turn) or trigger side effects such as logging and notifications. Unlike PreToolUse, PostToolUse cannot block — the tool has already executed. It is primarily used for observability: logging file writes, tracking command execution, or injecting warnings.

## Source
- [Automate Workflows with Hooks — Anthropic Docs](https://docs.anthropic.com/en/docs/claude-code/hooks-guide)

## Related
- PreToolUse
- [Lifecycle](/concepts/en/lifecycle.md)