diff --git a/hive-subagent-mcp/src/session.rs b/hive-subagent-mcp/src/session.rs
index a8d8dfae..545f9e7e 100644
--- a/hive-subagent-mcp/src/session.rs
+++ b/hive-subagent-mcp/src/session.rs
@@ -4113,8 +4113,10 @@ mod tests {
     /// An ACP agent in plain `sh`, after `hive-runtime`'s own test agent. It
     /// has one session, `s1`, appends every method it is sent to
     /// `<log>.methods` and every `session/prompt` line to `<log>`, and
-    /// answers each prompt with `end_turn` — or, in `hold` mode, only once
-    /// `session/cancel` arrives.
+    /// answers each prompt with `end_turn` and a token `usage` — or, in
+    /// `hold` mode, only once `session/cancel` arrives. The `usage` keeps a
+    /// plain reply from `hive_runtime::acp::AcpError::EmptyEndTurn`, the
+    /// same reason `hive-runtime`'s own test agent's replies carry one.
     const ACP_AGENT: &str = r#"
 prompt=
 while IFS= read -r line; do
@@ -4133,7 +4135,7 @@ while IFS= read -r line; do
       if [ "$2" = hold ]; then
         prompt=$id
       else
-        printf '{"jsonrpc":"2.0","id":%s,"result":{"stopReason":"end_turn"}}\n' "$id"
+        printf '{"jsonrpc":"2.0","id":%s,"result":{"stopReason":"end_turn","usage":{"inputTokens":1,"outputTokens":1}}}\n' "$id"
       fi ;;
     session/cancel)
       if [ -n "$prompt" ]; then