diff --git a/crates/uv-cli/src/lib.rs b/crates/uv-cli/src/lib.rs
index 37acc18a4077..5f168ab78d0d 100644
--- a/crates/uv-cli/src/lib.rs
+++ b/crates/uv-cli/src/lib.rs
@@ -2368,10 +2368,16 @@ pub struct SyncArgs {
     /// Include optional dependencies from the extra group name.
     ///
     /// May be provided more than once.
+    ///
+    /// Note that all optional dependencies are always included in the resolution; this option only
+    /// affects the selection of packages to install.
     #[arg(long, conflicts_with = "all_extras", value_parser = extra_name_with_clap_error)]
     pub extra: Option<Vec<ExtraName>>,
 
     /// Include all optional dependencies.
+    ///
+    /// Note that all optional dependencies are always included in the resolution; this option only
+    /// affects the selection of packages to install.
     #[arg(long, conflicts_with = "extra")]
     pub all_extras: bool,
 
diff --git a/docs/reference/cli.md b/docs/reference/cli.md
index 4ba82d500610..94008f4efce9 100644
--- a/docs/reference/cli.md
+++ b/docs/reference/cli.md
@@ -1132,7 +1132,9 @@ uv sync [OPTIONS]
 
 <h3 class="cli-reference">Options</h3>
 
-<dl class="cli-reference"><dt><code>--all-extras</code></dt><dd><p>Include all optional dependencies</p>
+<dl class="cli-reference"><dt><code>--all-extras</code></dt><dd><p>Include all optional dependencies.</p>
+
+<p>Note that all optional dependencies are always included in the resolution; this option only affects the selection of packages to install.</p>
 
 </dd><dt><code>--allow-insecure-host</code> <i>allow-insecure-host</i></dt><dd><p>Allow insecure connections to a host.</p>
 
@@ -1183,6 +1185,8 @@ uv sync [OPTIONS]
 
 <p>May be provided more than once.</p>
 
+<p>Note that all optional dependencies are always included in the resolution; this option only affects the selection of packages to install.</p>
+
 </dd><dt><code>--extra-index-url</code> <i>extra-index-url</i></dt><dd><p>Extra URLs of package indexes to use, in addition to <code>--index-url</code>.</p>
 
 <p>Accepts either a repository compliant with PEP 503 (the simple repository API), or a local directory laid out in the same format.</p>