fix: clarify Matrix E2EE prototype gates

Author: bglusman

crates/calciforge/src/channels/matrix.rs

@@ -654,8 +654,11 @@ pub async fn run(
             .await
             .with_context(|| format!("Matrix: room '{room_id_str}' not accessible"))?;
 
-        let is_encrypted =
-            check_room_encryption(&homeserver, &room_id_str, &http, &auth_header).await;
+        let is_encrypted = if channel.matrix_e2ee == MatrixE2eeMode::Off {
+            false
+        } else {
+            check_room_encryption(&homeserver, &room_id_str, &http, &auth_header).await
+        };
         if let Some(error) = matrix_e2ee_startup_error(channel.matrix_e2ee, true, is_encrypted) {
             anyhow::bail!("{error}");
         }

crates/calciforge/src/channels/matrix_e2ee.rs

@@ -8,8 +8,13 @@ use std::path::Path;
 
 use matrix_sdk::Client;
 
-// Kept compile-gated until the Matrix channel loop is SDK-backed.
-#[allow(dead_code)]
+#[cfg_attr(
+    not(test),
+    expect(
+        dead_code,
+        reason = "experimental SDK scaffold is compile-gated until the Matrix loop is SDK-backed"
+    )
+)]
 pub fn e2ee_client_builder(
     homeserver: &str,
     store_path: impl AsRef<Path>,

crates/calciforge/src/config.rs

@@ -398,9 +398,9 @@ pub struct ChannelConfig {
     /// Matrix end-to-end encryption handling.
     ///
     /// The production Matrix channel is still raw Client-Server API. Use
-    /// `warn` to keep today's behavior, `require` to fail closed when the
-    /// configured room is not encrypted, or `experimental-sdk` only on builds
-    /// compiled with `channel-matrix-e2ee`.
+    /// `warn` to keep today's behavior, `require` to fail closed unless an
+    /// SDK-backed encrypted runtime is available, or `experimental-sdk` only
+    /// on builds compiled with `channel-matrix-e2ee`.
     #[serde(default)]
     pub matrix_e2ee: MatrixE2eeMode,
 

crates/calciforge/src/config/validator.rs

@@ -269,7 +269,7 @@ fn validate_channels(config: &CalciforgeConfig, result: &mut ValidationResult) {
                 }
                 if channel.enabled && channel.allowed_users.is_empty() {
                     result.add_error(
-                        "Matrix channel requires at least one allowed_user when enabled"
+                        "Matrix channel requires at least one allowed_users entry when enabled"
                             .to_string(),
                     );
                 }
@@ -281,6 +281,12 @@ fn validate_channels(config: &CalciforgeConfig, result: &mut ValidationResult) {
                                     .to_string(),
                             );
                         }
+                        if channel.matrix_e2ee_store_passphrase_file.is_some() {
+                            result.add_warning(
+                                "Matrix channel sets matrix_e2ee_store_passphrase_file, but matrix_e2ee is not experimental-sdk; the passphrase file will be ignored"
+                                    .to_string(),
+                            );
+                        }
                     }
                     MatrixE2eeMode::Require => {
                         if channel.enabled && channel.room_id.is_none() {

docs/adr/0003-matrix-e2ee-prototype.md

@@ -5,7 +5,7 @@ title: "ADR 0003: Matrix E2EE Prototype"
 
 # ADR 0003: Matrix E2EE Prototype
 
-Status: Experimental branch note
+Status: Experimental
 
 Date: 2026-05-12