Match log levels exactly

src/cortex-cli/src/logs_cmd.rs

@@ -81,6 +81,15 @@ fn format_size(bytes: u64) -> String {
     }
 }
 
+fn parse_log_level(line: &str) -> Option<&str> {
+    line.split(|c: char| !c.is_ascii_alphanumeric())
+        .find(|part| matches!(*part, "TRACE" | "DEBUG" | "INFO" | "WARN" | "ERROR"))
+}
+
+fn line_matches_level(line: &str, level: &str) -> bool {
+    parse_log_level(&line.to_uppercase()).is_some_and(|line_level| line_level == level)
+}
+
 impl LogsCli {
     /// Run the logs command.
     pub async fn run(self) -> Result<()> {
@@ -174,7 +183,7 @@ impl LogsCli {
             let level_upper = level.to_uppercase();
             lines
                 .iter()
-                .filter(|line| line.to_uppercase().contains(&level_upper))
+                .filter(|line| line_matches_level(line, &level_upper))
                 .copied()
                 .collect()
         } else {
@@ -240,7 +249,7 @@ impl LogsCli {
                 Ok(_) => {
                     // Apply level filter if specified
                     if let Some(ref level) = level_filter
-                        && !line.to_uppercase().contains(&level.to_uppercase())
+                        && !line_matches_level(&line, &level.to_uppercase())
                     {
                         continue;
                     }

src/cortex-cli/tests/logs_level_filter.rs

@@ -0,0 +1,83 @@
+use std::fs;
+use std::process::Command;
+
+use tempfile::tempdir;
+
+fn combined_output(output: &std::process::Output) -> String {
+    format!(
+        "{}{}",
+        String::from_utf8_lossy(&output.stdout),
+        String::from_utf8_lossy(&output.stderr)
+    )
+}
+
+#[test]
+fn logs_level_filter_matches_exact_log_level() {
+    let home = tempdir().unwrap();
+    let cache = tempdir().unwrap();
+    let logs_dir = cache.path().join("cortex").join("logs");
+    fs::create_dir_all(&logs_dir).unwrap();
+    fs::write(
+        logs_dir.join("cortex.log"),
+        [
+            "2026-05-20T00:00:00Z INFO startup ok",
+            "2026-05-20T00:00:01Z WARN contains ERROR in the message",
+            "2026-05-20T00:00:02Z ERROR actual failure",
+            "",
+        ]
+        .join("\n"),
+    )
+    .unwrap();
+
+    let output = Command::new(env!("CARGO_BIN_EXE_Cortex"))
+        .args(["logs", "--level", "error", "--lines", "10"])
+        .env("HOME", home.path())
+        .env("XDG_CACHE_HOME", cache.path())
+        .env_remove("CORTEX_HOME")
+        .output()
+        .unwrap();
+
+    assert!(
+        output.status.success(),
+        "logs --level failed:\n{}",
+        combined_output(&output)
+    );
+
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    assert!(stdout.contains("ERROR actual failure"), "output:\n{stdout}");
+    assert!(!stdout.contains("WARN contains ERROR"), "output:\n{stdout}");
+    assert!(!stdout.contains("INFO startup"), "output:\n{stdout}");
+}
+
+#[test]
+fn logs_level_filter_does_not_match_partial_level() {
+    let home = tempdir().unwrap();
+    let cache = tempdir().unwrap();
+    let logs_dir = cache.path().join("cortex").join("logs");
+    fs::create_dir_all(&logs_dir).unwrap();
+    fs::write(
+        logs_dir.join("cortex.log"),
+        "2026-05-20T00:00:00Z ERROR actual failure\n",
+    )
+    .unwrap();
+
+    let output = Command::new(env!("CARGO_BIN_EXE_Cortex"))
+        .args(["logs", "--level", "err", "--lines", "10"])
+        .env("HOME", home.path())
+        .env("XDG_CACHE_HOME", cache.path())
+        .env_remove("CORTEX_HOME")
+        .output()
+        .unwrap();
+
+    assert!(
+        output.status.success(),
+        "logs --level failed:\n{}",
+        combined_output(&output)
+    );
+
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    assert!(
+        !stdout.contains("ERROR actual failure"),
+        "output:\n{stdout}"
+    );
+}