diff --git a/Cargo.lock b/Cargo.lock
index a481ac8..2f3d8d5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -427,6 +427,7 @@ dependencies = [
  "codebook_config",
  "env_logger",
  "fs2",
+ "glob",
  "log",
  "lru",
  "serde",
@@ -436,6 +437,7 @@ dependencies = [
  "tempfile",
  "tokio",
  "tower-lsp",
+ "walkdir",
 ]
 
 [[package]]
diff --git a/crates/codebook-lsp/Cargo.toml b/crates/codebook-lsp/Cargo.toml
index b621344..27d1a11 100644
--- a/crates/codebook-lsp/Cargo.toml
+++ b/crates/codebook-lsp/Cargo.toml
@@ -28,6 +28,8 @@ env_logger.workspace = true
 fs2.workspace = true
 log.workspace = true
 lru.workspace = true
+glob.workspace = true
+walkdir.workspace = true
 serde.workspace = true
 serde_json.workspace = true
 string-offsets.workspace = true
diff --git a/crates/codebook-lsp/src/lint.rs b/crates/codebook-lsp/src/lint.rs
new file mode 100644
index 0000000..3ecd5ab
--- /dev/null
+++ b/crates/codebook-lsp/src/lint.rs
@@ -0,0 +1,215 @@
+use codebook::Codebook;
+use codebook_config::{CodebookConfig, CodebookConfigFile};
+use std::collections::HashSet;
+use std::io::{IsTerminal, Write};
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+
+struct Styles {
+    bold: &'static str,
+    dim: &'static str,
+    yellow: &'static str,
+    bold_red: &'static str,
+    reset: &'static str,
+}
+
+const STYLES_ON: Styles = Styles {
+    bold: "\x1b[1m",
+    dim: "\x1b[2m",
+    yellow: "\x1b[33m",
+    bold_red: "\x1b[1;31m",
+    reset: "\x1b[0m",
+};
+
+const STYLES_OFF: Styles = Styles {
+    bold: "",
+    dim: "",
+    yellow: "",
+    bold_red: "",
+    reset: "",
+};
+
+fn styles(is_terminal: bool) -> &'static Styles {
+    if is_terminal && std::env::var_os("NO_COLOR").is_none() {
+        &STYLES_ON
+    } else {
+        &STYLES_OFF
+    }
+}
+
+fn fatal(msg: impl std::fmt::Display, s: &Styles) -> ! {
+    eprintln!("{}error:{} {msg}", s.bold_red, s.reset);
+    std::process::exit(2);
+}
+
+pub fn run_lint(files: &[String], root: &Path, unique: bool) -> bool {
+    let out = styles(std::io::stdout().is_terminal());
+    let err = styles(std::io::stderr().is_terminal());
+
+    let config = Arc::new(
+        CodebookConfigFile::load(Some(root))
+            .unwrap_or_else(|e| fatal(format!("failed to load config: {e}"), err)),
+    );
+
+    print_config_source(&config, err);
+
+    let codebook = Codebook::new(config.clone())
+        .unwrap_or_else(|e| fatal(format!("failed to initialize: {e}"), err));
+
+    let resolved = resolve_paths(files);
+    if resolved.is_empty() {
+        fatal("no files matched the given patterns", err);
+    }
+
+    let mut seen_words: HashSet<String> = HashSet::new();
+    let mut total_errors = 0usize;
+    let mut files_with_errors = 0usize;
+
+    for path in &resolved {
+        if config.should_ignore_path(path) {
+            continue;
+        }
+
+        let text = match std::fs::read_to_string(path) {
+            Ok(t) => t,
+            Err(e) => {
+                eprintln!(
+                    "{}error:{} {}: {e}",
+                    err.bold_red,
+                    err.reset,
+                    path.display()
+                );
+                continue;
+            }
+        };
+
+        let mut locations = codebook.spell_check(&text, None, path.to_str());
+        locations.sort_by_key(|l| l.locations.first().map(|r| r.start_byte).unwrap_or(0));
+
+        let hits: Vec<(usize, usize, &str)> = locations
+            .iter()
+            .flat_map(|wl| wl.locations.iter().map(move |r| (wl, r)))
+            .filter_map(|(wl, range)| {
+                if unique && !seen_words.insert(wl.word.to_lowercase()) {
+                    return None;
+                }
+                let (line, col) = byte_offset_to_line_col(&text, range.start_byte);
+                Some((line, col, wl.word.as_str()))
+            })
+            .collect();
+
+        if hits.is_empty() {
+            continue;
+        }
+
+        let raw = path.to_string_lossy();
+        let display = raw.strip_prefix("./").unwrap_or(&raw);
+        let pad_len = hits
+            .iter()
+            .map(|(l, c, _)| format!("{l}:{c}").len())
+            .max()
+            .unwrap_or(0);
+
+        println!("{}{display}{}", out.bold, out.reset);
+        for (line, col, word) in &hits {
+            let loc = format!("{line}:{col}");
+            println!(
+                "  {}{display}{}:{}{loc}{}{pad}  {}{}{}",
+                out.dim,
+                out.reset,
+                out.yellow,
+                out.reset,
+                out.bold_red,
+                word,
+                out.reset,
+                pad = " ".repeat(pad_len - loc.len()),
+            );
+        }
+        println!();
+
+        total_errors += hits.len();
+        files_with_errors += 1;
+    }
+
+    if total_errors > 0 {
+        let _ = std::io::stdout().flush();
+        let unique_label = if unique { "unique " } else { "" };
+        eprintln!(
+            "Found {}{total_errors}{} {unique_label}spelling error(s) in {}{files_with_errors}{} file(s).",
+            err.bold, err.reset, err.bold, err.reset,
+        );
+    }
+
+    total_errors > 0
+}
+
+fn print_config_source(config: &CodebookConfigFile, s: &Styles) {
+    let cwd = std::env::current_dir().unwrap_or_default();
+    match (
+        config.project_config_path().filter(|p| p.is_file()),
+        config.global_config_path().filter(|p| p.is_file()),
+    ) {
+        (Some(p), _) => eprintln!(
+            "using config {}{}{}",
+            s.dim,
+            p.strip_prefix(&cwd).unwrap_or(&p).display(),
+            s.reset
+        ),
+        (None, Some(g)) => eprintln!(
+            "using global config {}{}{}",
+            s.dim,
+            g.strip_prefix(&cwd).unwrap_or(&g).display(),
+            s.reset
+        ),
+        (None, None) => eprintln!("using default config"),
+    }
+}
+
+fn resolve_paths(patterns: &[String]) -> Vec<PathBuf> {
+    let mut paths = Vec::new();
+    for pattern in patterns {
+        let p = PathBuf::from(pattern);
+        if p.is_dir() {
+            collect_dir(&p, &mut paths);
+        } else {
+            match glob::glob(pattern) {
+                Ok(entries) => {
+                    let mut matched = false;
+                    for entry in entries.flatten() {
+                        if entry.is_file() {
+                            paths.push(entry);
+                            matched = true;
+                        } else if entry.is_dir() {
+                            collect_dir(&entry, &mut paths);
+                            matched = true;
+                        }
+                    }
+                    if !matched {
+                        eprintln!("codebook: no match for '{pattern}'");
+                    }
+                }
+                Err(e) => eprintln!("codebook: invalid pattern '{pattern}': {e}"),
+            }
+        }
+    }
+    paths.sort();
+    paths.dedup();
+    paths
+}
+
+fn collect_dir(dir: &Path, out: &mut Vec<PathBuf>) {
+    walkdir::WalkDir::new(dir)
+        .follow_links(false)
+        .into_iter()
+        .flatten()
+        .filter(|e| e.file_type().is_file())
+        .for_each(|e| out.push(e.into_path()));
+}
+
+fn byte_offset_to_line_col(text: &str, byte_offset: usize) -> (usize, usize) {
+    let offset = byte_offset.min(text.len());
+    let before = &text[..offset];
+    let line = before.bytes().filter(|&b| b == b'\n').count() + 1;
+    let col = before.rfind('\n').map(|p| offset - p).unwrap_or(offset + 1);
+    (line, col)
+}
diff --git a/crates/codebook-lsp/src/main.rs b/crates/codebook-lsp/src/main.rs
index bc055ee..c6898c4 100644
--- a/crates/codebook-lsp/src/main.rs
+++ b/crates/codebook-lsp/src/main.rs
@@ -1,5 +1,6 @@
 mod file_cache;
 mod init_options;
+mod lint;
 mod lsp;
 mod lsp_logger;
 
@@ -30,6 +31,15 @@ enum Commands {
     Serve {},
     /// Remove server cache
     Clean {},
+    /// Check files for spelling errors
+    Lint {
+        /// Files or glob patterns to spell-check
+        #[arg(required = true)]
+        files: Vec<String>,
+        /// Only report each misspelled word once, ignoring duplicates across files
+        #[arg(short = 'u', long)]
+        unique: bool,
+    },
 }
 
 #[tokio::main(flavor = "current_thread")]
@@ -58,6 +68,11 @@ async fn main() {
             info!("Cleaning: {:?}", config.cache_dir);
             config.clean_cache()
         }
+        Some(Commands::Lint { files, unique }) => {
+            if lint::run_lint(files, root, *unique) {
+                std::process::exit(1);
+            }
+        }
         None => {}
     }
 }