diff --git a/.changeset/skill-document-update-all-flag.md b/.changeset/skill-document-update-all-flag.md
new file mode 100644
index 00000000..75e66ae3
--- /dev/null
+++ b/.changeset/skill-document-update-all-flag.md
@@ -0,0 +1,5 @@
+---
+"clerk": patch
+---
+
+Document the `--all` flag for `clerk update` in the bundled Clerk agent skill's command reference table. The flag was already implemented but missing from the skill, so agents couldn't help users with multiple clerk installs on PATH.
diff --git a/skills/clerk/SKILL.md b/skills/clerk/SKILL.md
index 0ce9f6f3..6e263358 100644
--- a/skills/clerk/SKILL.md
+++ b/skills/clerk/SKILL.md
@@ -138,7 +138,7 @@ See [references/recipes.md](references/recipes.md) for concrete patterns: listin
 | `clerk api [path]`         | Authenticated HTTP to Backend/Platform API.                                                                                                                                  | `-X`, `-d`, `--file`, `--dry-run`, `--yes`, `--include`, `--app`, `--secret-key`, `--instance`, `--platform` |
 | `clerk api ls [filter]`    | Discover endpoints from the bundled OpenAPI catalog.                                                                                                                         | `--platform`                                                                                                 |
 | `clerk completion [shell]` | Print a shell completion script (`bash`, `zsh`, `fish`, `powershell`).                                                                                                       | —                                                                                                            |
-| `clerk update`             | Update the CLI to the latest version.                                                                                                                                        | `--channel`, `-y`                                                                                            |
+| `clerk update`             | Update the CLI to the latest version.                                                                                                                                        | `--channel`, `-y`, `--all`                                                                                   |
 | `clerk skill install`      | Reinstall the bundled `clerk` skill. Run after upgrading the CLI so the skill matches the new binary.                                                                        | `-y`, `--pm`                                                                                                 |
 
 **`clerk <command> --help` is the source of truth for flags.** This table is a hint, not a spec. Before running an unfamiliar command or flag combination, run `clerk <command> --help` once per session. Every command also defines `setExamples([...])` in source, which `--help` renders as a copy-pasteable Examples block, so you rarely need to guess syntax.