---
title: 5.2 Hook Server Flag Ignored
permalink: 5-reference/hook-server-flag-ignored
publish: true
visibility: public
tags:
  - manual
garden-url: https://francisfontaine.com/5-reference/hook-server-flag-ignored
garden-short: https://stnd.gd/jGxtCD
created: 2026-07-29T19:39:12.626Z
modified: 2026-08-06T21:41:02.845Z
---

# Hook Server Flag Ignored

> **Error:** `Hook "X" (module "Y") sets "server: true", but this hook classifies as a UI/action zone contribution, which has no server/client split.`

## The Problem

A hook entry sets `{ server: true }` under a hook name that classifies as a **UI/action zone contribution** — any `launcher:`-prefixed or `:action`-suffixed hook name, regardless of entry type (see [hook-kind-mismatch](hook-kind-mismatch.md) for the full classification rule).

## The Why

`server: true` excludes a hook entry from the client bundle — but only for **logic hooks**, compiled into `virtual:stnd/hooks`, which resolves to a different virtual module for SSR vs. the client build (`generateHooksModule({ ssr })` filters `server: true` entries out of the client version).

UI/action zone contributions compile into `virtual:stnd/components` instead, which has no SSR/client split at all — it's the same single module in both contexts, because it's also read directly by client-bundled code (`packages/launcher/launcher.ts` for `launcher:action`, `GraftToolbar.svelte` for `graft:action`) that needs the actual function reference to call on click, not just server-rendered output.

Before this check existed, `server: true` on one of these entries was silently accepted and did nothing — the entry still shipped into the client bundle exactly as if the flag weren't there. That's a dangerous kind of silence: a developer marking a handler `server: true` is very likely doing it because the handler touches something sensitive (a DB call, a secret, server-only auth state), and a no-op safety flag gives false confidence that it's protected when it isn't.

## The Solution

1. **Remove `server: true`** if this handler is genuinely meant to run client-side (the common case for `launcher:action`/`graft:action` — they're click handlers).
2. **Rename the hook off the `launcher:`/`:action` pattern** if it must stay server-only. Logic hooks support `server: true` correctly — see [modules](modules.md#hooks--ui-zones) for the `runHook`/`runPipeline` two-way split.
3. **Move server-only work behind `astro:actions`** instead, if what you actually need is "a client can trigger this, but the sensitive part runs server-side" — that's what Astro Actions are for, and it's the pattern this framework's own `billing` module already uses (`actions: "./actions.ts"`, unrelated to the `hooks:` classification this error is about).

## Related Concepts

- [hook-kind-mismatch](hook-kind-mismatch.md): The classification rule that determines which hooks this flag applies to.
- [modules](modules.md): The full module manifest API, including `hooks:`.