diff --git a/Cargo.lock b/Cargo.lock
index 7fc398e..7c9df60 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -682,9 +682,13 @@ dependencies = [
 name = "mabo-cli"
 version = "0.1.0"
 dependencies = [
+ "anyhow",
  "clap",
  "glob",
+ "mabo-compiler",
+ "mabo-doc",
  "mabo-parser",
+ "mabo-project",
  "miette",
  "mimalloc",
 ]
diff --git a/book/.vitepress/config.mts b/book/.vitepress/config.mts
index b012843..7b0e0e7 100644
--- a/book/.vitepress/config.mts
+++ b/book/.vitepress/config.mts
@@ -85,7 +85,8 @@ export default defineConfig({
             items: [
               { text: "mabo lint", link: "/reference/cli/lint" },
               { text: "mabo check", link: "/reference/cli/check" },
-              { text: "mabo format", link: "/reference/cli/format" },
+              { text: "mabo fmt", link: "/reference/cli/fmt" },
+              { text: "mabo doc", link: "/reference/cli/doc" },
             ],
           },
           {
diff --git a/book/src/reference/cli/check.md b/book/src/reference/cli/check.md
index e69de29..2c909ee 100644
--- a/book/src/reference/cli/check.md
+++ b/book/src/reference/cli/check.md
@@ -0,0 +1 @@
+# mabo check
diff --git a/book/src/reference/cli/doc.md b/book/src/reference/cli/doc.md
new file mode 100644
index 0000000..56306b3
--- /dev/null
+++ b/book/src/reference/cli/doc.md
@@ -0,0 +1 @@
+# mabo doc
diff --git a/book/src/reference/cli/fmt.md b/book/src/reference/cli/fmt.md
new file mode 100644
index 0000000..8e57d52
--- /dev/null
+++ b/book/src/reference/cli/fmt.md
@@ -0,0 +1 @@
+# mabo fmt
diff --git a/book/src/reference/cli/format.md b/book/src/reference/cli/format.md
deleted file mode 100644
index e69de29..0000000
diff --git a/book/src/reference/cli/lint.md b/book/src/reference/cli/lint.md
index e69de29..9951adf 100644
--- a/book/src/reference/cli/lint.md
+++ b/book/src/reference/cli/lint.md
@@ -0,0 +1 @@
+# mabo lint
diff --git a/crates/mabo-benches/Cargo.toml b/crates/mabo-benches/Cargo.toml
index 1213b0d..96b48e3 100644
--- a/crates/mabo-benches/Cargo.toml
+++ b/crates/mabo-benches/Cargo.toml
@@ -23,9 +23,9 @@ name = "varint"
 harness = false
 
 [dependencies]
-mimalloc.workspace = true
 mabo-compiler = { path = "../mabo-compiler" }
 mabo-parser = { path = "../mabo-parser" }
+mimalloc.workspace = true
 
 [dev-dependencies]
 divan = "0.1.8"
diff --git a/crates/mabo-build/Cargo.toml b/crates/mabo-build/Cargo.toml
index 59eee8a..59cb2b6 100644
--- a/crates/mabo-build/Cargo.toml
+++ b/crates/mabo-build/Cargo.toml
@@ -10,13 +10,13 @@ repository.workspace = true
 license.workspace = true
 
 [dependencies]
+mabo-compiler = { path = "../mabo-compiler" }
+mabo-parser = { path = "../mabo-parser" }
+mabo-project = { path = "../mabo-project" }
 miette = { workspace = true, features = ["fancy-no-backtrace"] }
 prettyplease = "0.2.16"
 proc-macro2.workspace = true
 quote.workspace = true
-mabo-compiler = { path = "../mabo-compiler" }
-mabo-parser = { path = "../mabo-parser" }
-mabo-project = { path = "../mabo-project" }
 syn.workspace = true
 thiserror.workspace = true
 
diff --git a/crates/mabo-cli/Cargo.toml b/crates/mabo-cli/Cargo.toml
index f1e6d62..b0be118 100644
--- a/crates/mabo-cli/Cargo.toml
+++ b/crates/mabo-cli/Cargo.toml
@@ -14,11 +14,15 @@ name = "mabo"
 path = "src/main.rs"
 
 [dependencies]
+anyhow.workspace = true
 clap.workspace = true
 glob.workspace = true
+mabo-compiler = { path = "../mabo-compiler" }
+mabo-doc = { path = "../mabo-doc" }
+mabo-parser = { path = "../mabo-parser" }
+mabo-project = { path = "../mabo-project" }
 miette = { workspace = true, features = ["fancy-no-backtrace"] }
 mimalloc.workspace = true
-mabo-parser = { path = "../mabo-parser" }
 
 [lints]
 workspace = true
diff --git a/crates/mabo-cli/src/cli.rs b/crates/mabo-cli/src/cli.rs
index e34a597..5ac7063 100644
--- a/crates/mabo-cli/src/cli.rs
+++ b/crates/mabo-cli/src/cli.rs
@@ -1,6 +1,6 @@
 use std::path::PathBuf;
 
-use clap::{Parser, Subcommand};
+use clap::{Args, Parser, Subcommand};
 
 #[derive(Parser)]
 #[command(about, author, version, propagate_version = true)]
@@ -11,17 +11,45 @@ pub struct Cli {
 
 #[derive(Subcommand)]
 pub enum Command {
-    Init {
-        path: Option<PathBuf>,
-    },
-    Check {
-        #[arg(num_args(1..))]
-        files: Vec<String>,
-    },
-    Format {
-        #[arg(num_args(1..))]
-        files: Vec<String>,
-    },
+    #[command(alias = "initialize")]
+    Init(InitArgs),
+    Check(CheckArgs),
+    #[command(alias = "format")]
+    Fmt(FmtArgs),
+    #[command(alias = "document")]
+    Doc(DocArgs),
+}
+
+/// Arguments for the [`Command::Init`] subcommand.
+#[derive(Args)]
+pub struct InitArgs {
+    #[arg(long)]
+    pub name: Option<String>,
+    pub path: Option<PathBuf>,
+}
+
+/// Arguments for the [`Command::Check`] subcommand.
+#[derive(Args)]
+pub struct CheckArgs {
+    #[arg(long)]
+    pub project_dir: Option<PathBuf>,
+    pub files: Vec<String>,
+}
+
+/// Arguments for the [`Command::Fmt`] subcommand.
+#[derive(Args)]
+pub struct FmtArgs {
+    #[arg(long)]
+    pub project_dir: Option<PathBuf>,
+    pub files: Vec<String>,
+}
+
+/// Arguments for the [`Command::Doc`] subcommand.
+#[derive(Args)]
+pub struct DocArgs {
+    #[arg(long)]
+    pub project_dir: Option<PathBuf>,
+    pub out_dir: PathBuf,
 }
 
 impl Cli {
diff --git a/crates/mabo-cli/src/main.rs b/crates/mabo-cli/src/main.rs
index 818a4e1..feefe06 100644
--- a/crates/mabo-cli/src/main.rs
+++ b/crates/mabo-cli/src/main.rs
@@ -1,11 +1,16 @@
 //! Main command line interface for tooling support of Mabo schema files.
 
-use std::{fs, process::ExitCode};
+use std::{
+    fs,
+    path::{Path, PathBuf},
+    process::ExitCode,
+};
 
+use anyhow::Context;
 use mabo_parser::Schema;
-use miette::{Context, IntoDiagnostic, Result};
+use miette::Context as _;
 
-use self::cli::Cli;
+use self::cli::{CheckArgs, Cli, DocArgs, FmtArgs};
 
 mod cli;
 
@@ -17,12 +22,13 @@ fn main() -> ExitCode {
 
     if let Some(cmd) = cli.cmd {
         let result = match cmd {
-            cli::Command::Init { path } => {
-                println!("TODO: create basic setup at {path:?}");
+            cli::Command::Init(args) => {
+                println!("TODO: create basic setup at {:?}", args.path);
                 Ok(())
             }
-            cli::Command::Check { files } => check(files),
-            cli::Command::Format { files } => format(files),
+            cli::Command::Check(args) => check(args),
+            cli::Command::Fmt(args) => format(args),
+            cli::Command::Doc(args) => doc(args),
         };
 
         return match result {
@@ -37,51 +43,92 @@ fn main() -> ExitCode {
     ExitCode::SUCCESS
 }
 
-fn check(patterns: Vec<String>) -> Result<()> {
-    for pattern in patterns {
-        for entry in glob::glob(&pattern)
-            .into_diagnostic()
-            .wrap_err("Failed parsing glob pattern")?
-        {
-            let entry = entry.into_diagnostic().wrap_err("Failed reading entry")?;
-            let buf = fs::read_to_string(&entry)
-                .into_diagnostic()
-                .wrap_err_with(|| format!("Failed reading {entry:?}"))?;
-
-            if let Err(e) = Schema::parse(&buf, Some(&entry)).wrap_err("Failed parsing schema file")
-            {
-                eprintln!("{e:?}");
-            }
+fn check(args: CheckArgs) -> anyhow::Result<()> {
+    for file in project_or_files(args.project_dir, args.files)? {
+        let buf = fs::read_to_string(&file).with_context(|| format!("failed reading {file:?}"))?;
+
+        if let Err(e) = Schema::parse(&buf, Some(&file)).wrap_err("failed parsing schema file") {
+            eprintln!("{e:?}");
         }
     }
 
     Ok(())
 }
 
-fn format(patterns: Vec<String>) -> Result<()> {
-    for pattern in patterns {
-        for entry in glob::glob(&pattern)
-            .into_diagnostic()
-            .wrap_err("Failed parsing glob pattern")?
-        {
-            let entry = entry.into_diagnostic().wrap_err("Failed reading entry")?;
-            let buf = fs::read_to_string(&entry).into_diagnostic()?;
-            let schema =
-                match Schema::parse(&buf, Some(&entry)).wrap_err("Failed parsing schema file") {
-                    Ok(schema) => schema,
-                    Err(e) => {
-                        eprintln!("{e:?}");
-                        continue;
-                    }
-                };
-
-            let formatted = schema.to_string();
-
-            if buf != formatted {
-                fs::write(entry, &formatted).into_diagnostic()?;
+fn format(args: FmtArgs) -> anyhow::Result<()> {
+    for file in project_or_files(args.project_dir, args.files)? {
+        let buf = fs::read_to_string(&file)?;
+        let schema = match Schema::parse(&buf, Some(&file)).wrap_err("Failed parsing schema file") {
+            Ok(schema) => schema,
+            Err(e) => {
+                eprintln!("{e:?}");
+                continue;
             }
+        };
+
+        let formatted = schema.to_string();
+
+        if buf != formatted {
+            fs::write(file, &formatted)?;
         }
     }
 
     Ok(())
 }
+
+fn doc(args: DocArgs) -> anyhow::Result<()> {
+    let project = mabo_project::load(project_dir(args.project_dir)?)?;
+
+    for file in project.files {
+        let content = std::fs::read_to_string(&file)?;
+        let schema = mabo_parser::Schema::parse(&content, Some(&file))?;
+        let schema = mabo_compiler::simplify_schema(&schema);
+        let docs = mabo_doc::render_schema(&mabo_doc::Opts {}, &schema)?;
+
+        write_doc_output(&docs, &args.out_dir.join(docs.name))?;
+    }
+
+    Ok(())
+}
+
+fn write_doc_output(output: &mabo_doc::Output<'_>, parent: &Path) -> anyhow::Result<()> {
+    let path = parent.join(output.name);
+    let file = parent.join(&output.file);
+
+    fs::create_dir_all(file.parent().unwrap())?;
+    fs::write(file, &output.content)?;
+
+    for module in &output.modules {
+        write_doc_output(module, &path)?;
+    }
+
+    Ok(())
+}
+
+fn project_or_files(
+    project: Option<PathBuf>,
+    patterns: Vec<String>,
+) -> anyhow::Result<Vec<PathBuf>> {
+    Ok(if patterns.is_empty() {
+        mabo_project::load(project_dir(project)?)?.files
+    } else {
+        let mut files = Vec::new();
+        for pattern in patterns {
+            for entry in glob::glob(&pattern).context("failed parsing glob pattern")? {
+                let entry = entry.context("failed reading entry")?;
+                if !entry.extension().map_or(false, |ext| ext == "mabo") {
+                    continue;
+                }
+                files.push(entry);
+            }
+        }
+        files
+    })
+}
+
+fn project_dir(arg: Option<PathBuf>) -> anyhow::Result<PathBuf> {
+    arg.map_or_else(
+        || std::env::current_dir().context("failed finding current directory"),
+        Ok,
+    )
+}
diff --git a/crates/mabo-compiler/Cargo.toml b/crates/mabo-compiler/Cargo.toml
index bfa1b0b..b0404c8 100644
--- a/crates/mabo-compiler/Cargo.toml
+++ b/crates/mabo-compiler/Cargo.toml
@@ -12,11 +12,11 @@ license.workspace = true
 [dependencies]
 anstream.workspace = true
 anstyle.workspace = true
+mabo-parser = { path = "../mabo-parser" }
 miette.workspace = true
 schemars = { version = "0.8.16", optional = true }
 serde = { workspace = true, optional = true }
 serde_json = { workspace = true, optional = true }
-mabo-parser = { path = "../mabo-parser" }
 thiserror.workspace = true
 
 [dev-dependencies]
diff --git a/crates/mabo-go/Cargo.toml b/crates/mabo-go/Cargo.toml
index e32caa5..0fe0aed 100644
--- a/crates/mabo-go/Cargo.toml
+++ b/crates/mabo-go/Cargo.toml
@@ -10,14 +10,14 @@ repository.workspace = true
 license.workspace = true
 
 [dependencies]
+anyhow.workspace = true
 clap.workspace = true
 heck = "0.4.1"
-miette = { workspace = true, features = ["fancy-no-backtrace"] }
 mabo-compiler = { path = "../mabo-compiler" }
 mabo-parser = { path = "../mabo-parser" }
 mabo-project = { path = "../mabo-project" }
+miette = { workspace = true, features = ["fancy-no-backtrace"] }
 mimalloc.workspace = true
-anyhow.workspace = true
 
 [dev-dependencies]
 insta.workspace = true
diff --git a/crates/mabo-lsp/Cargo.toml b/crates/mabo-lsp/Cargo.toml
index ff99fc4..9ade9e9 100644
--- a/crates/mabo-lsp/Cargo.toml
+++ b/crates/mabo-lsp/Cargo.toml
@@ -17,15 +17,15 @@ line-index = "0.1.1"
 log = { version = "0.4.20", features = ["kv_unstable_std", "std"] }
 lsp-server = "0.7.6"
 lsp-types = { version = "0.95.0", features = ["proposed"] }
-ouroboros = "0.18.2"
-parking_lot = "0.12.1"
-ropey = "1.6.1"
-serde.workspace = true
-serde_json.workspace = true
 mabo-compiler = { path = "../mabo-compiler" }
 mabo-meta = { path = "../mabo-meta" }
 mabo-parser = { path = "../mabo-parser" }
 mabo-project = { path = "../mabo-project" }
+ouroboros = "0.18.2"
+parking_lot = "0.12.1"
+ropey = "1.6.1"
+serde_json.workspace = true
+serde.workspace = true
 time = { version = "0.3.31", features = ["formatting", "local-offset", "macros"] }
 
 [lints]
diff --git a/crates/mabo-parser/Cargo.toml b/crates/mabo-parser/Cargo.toml
index 5616114..119e7c3 100644
--- a/crates/mabo-parser/Cargo.toml
+++ b/crates/mabo-parser/Cargo.toml
@@ -15,8 +15,8 @@ rustc-args = ["--cfg", "docsrs"]
 [dependencies]
 anstream.workspace = true
 anstyle.workspace = true
-miette.workspace = true
 mabo-derive = { path = "../mabo-derive" }
+miette.workspace = true
 winnow = "0.5.33"
 
 [dev-dependencies]