Category option for signature (#343)

* category option for signature

* category option for signature

* column description for $scope

crates/nu-command/src/conversions/into/binary.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::{
     ast::{Call, CellPath},
     engine::{Command, EngineState, Stack},
-    Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -14,11 +14,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("into binary").rest(
+        Signature::build("into binary")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "column paths to convert to binary (for table input)",
+                SyntaxShape::CellPath,
-        )
+                "column paths to convert to binary (for table input)",
+            )
+            .category(Category::Conversions)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/conversions/into/command.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Value,
 };
 
 #[derive(Clone)]
@@ -14,7 +14,7 @@ impl Command for Into {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("into")
+        Signature::build("into").category(Category::Conversions)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/conversions/into/filesize.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::{
     ast::{Call, CellPath},
     engine::{Command, EngineState, Stack},
-    Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -14,11 +14,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("into filesize").rest(
+        Signature::build("into filesize")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "column paths to convert to filesize (for table input)",
+                SyntaxShape::CellPath,
-        )
+                "column paths to convert to filesize (for table input)",
+            )
+            .category(Category::Conversions)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/conversions/into/int.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::{
     ast::{Call, CellPath},
     engine::{Command, EngineState, Stack},
-    Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -14,11 +14,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("into int").rest(
+        Signature::build("into int")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "column paths to convert to int (for table input)",
+                SyntaxShape::CellPath,
-        )
+                "column paths to convert to int (for table input)",
+            )
+            .category(Category::Conversions)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/conversions/into/string.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::{
     ast::{Call, CellPath},
     engine::{Command, EngineState, Stack},
-    Config, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Config, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
 };
 
 // TODO num_format::SystemLocale once platform-specific dependencies are stable (see Cargo.toml)
@@ -29,6 +29,7 @@ impl Command for SubCommand {
                 "decimal digits to which to round",
                 Some('d'),
             )
+            .category(Category::Conversions)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/core_commands/alias.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Alias;
@@ -22,6 +22,7 @@ impl Command for Alias {
                 SyntaxShape::Keyword(b"=".to_vec(), Box::new(SyntaxShape::Expression)),
                 "equals sign followed by value",
             )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/def.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Def;
@@ -23,6 +23,7 @@ impl Command for Def {
                 SyntaxShape::Block(Some(vec![])),
                 "body of the definition",
             )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/do_.rs

@@ -1,7 +1,7 @@
 use nu_engine::{eval_block, CallExt};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape, Value};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape, Value};
 
 #[derive(Clone)]
 pub struct Do;
@@ -24,6 +24,7 @@ impl Command for Do {
                 "the block to run",
             )
             .rest("rest", SyntaxShape::Any, "the parameter(s) for the block")
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/echo.rs

@@ -1,7 +1,9 @@
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, SyntaxShape, Value, ValueStream};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Value, ValueStream,
+};
 
 #[derive(Clone)]
 pub struct Echo;
@@ -16,7 +18,9 @@ impl Command for Echo {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("echo").rest("rest", SyntaxShape::Any, "the values to echo")
+        Signature::build("echo")
+            .rest("rest", SyntaxShape::Any, "the values to echo")
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/export.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Value,
 };
 
 #[derive(Clone)]
@@ -14,7 +14,7 @@ impl Command for ExportCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("export")
+        Signature::build("export").category(Category::Core)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/core_commands/export_def.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct ExportDef;
@@ -23,6 +23,7 @@ impl Command for ExportDef {
                 SyntaxShape::Block(Some(vec![])),
                 "body of the definition",
             )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/export_env.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct ExportEnv;
@@ -26,6 +26,7 @@ impl Command for ExportEnv {
                 SyntaxShape::Block(Some(vec![])),
                 "body of the environment variable definition",
             )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/for_.rs

@@ -2,7 +2,8 @@ use nu_engine::{eval_block, eval_expression};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, PipelineData, Signature, Span, SyntaxShape, Value,
+    Category, Example, IntoInterruptiblePipelineData, PipelineData, Signature, Span, SyntaxShape,
+    Value,
 };
 
 #[derive(Clone)]
@@ -35,6 +36,7 @@ impl Command for For {
                 "the block to run",
             )
             .creates_scope()
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/help.rs

@@ -1,8 +1,8 @@
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    span, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError,
+    span, Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData,
-    Signature, Spanned, SyntaxShape, Value,
+    ShellError, Signature, Spanned, SyntaxShape, Value,
 };
 
 use nu_engine::{get_full_help, CallExt};
@@ -28,6 +28,7 @@ impl Command for Help {
                 "string to find in command usage",
                 Some('f'),
             )
+            .category(Category::Core)
     }
 
     fn usage(&self) -> &str {
@@ -107,6 +108,12 @@ fn help(
                     span: head,
                 });
 
+                cols.push("category".into());
+                vals.push(Value::String {
+                    val: cmd.0.category.to_string(),
+                    span: head,
+                });
+
                 cols.push("usage".into());
                 vals.push(Value::String { val: c, span: head });
 
@@ -144,6 +151,12 @@ fn help(
                     span: head,
                 });
 
+                cols.push("category".into());
+                vals.push(Value::String {
+                    val: cmd.0.category.to_string(),
+                    span: head,
+                });
+
                 cols.push("usage".into());
                 vals.push(Value::String { val: c, span: head });
 

crates/nu-command/src/core_commands/hide.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Hide;
@@ -10,12 +10,14 @@ impl Command for Hide {
         "hide"
     }
 
-    fn usage(&self) -> &str {
+    fn signature(&self) -> nu_protocol::Signature {
-        "Hide definitions in the current scope"
+        Signature::build("hide")
+            .required("pattern", SyntaxShape::String, "import pattern")
+            .category(Category::Core)
     }
 
-    fn signature(&self) -> nu_protocol::Signature {
+    fn usage(&self) -> &str {
-        Signature::build("hide").required("pattern", SyntaxShape::String, "import pattern")
+        "Hide definitions in the current scope"
     }
 
     fn run(

crates/nu-command/src/core_commands/if_.rs

@@ -1,7 +1,9 @@
 use nu_engine::{eval_block, eval_expression};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoPipelineData, PipelineData, ShellError, Signature, SyntaxShape, Value};
+use nu_protocol::{
+    Category, IntoPipelineData, PipelineData, ShellError, Signature, SyntaxShape, Value,
+};
 
 #[derive(Clone)]
 pub struct If;
@@ -24,6 +26,7 @@ impl Command for If {
                 SyntaxShape::Keyword(b"else".to_vec(), Box::new(SyntaxShape::Expression)),
                 "optional else followed by else block",
             )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/let_.rs

@@ -1,7 +1,7 @@
 use nu_engine::eval_expression;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Let;
@@ -23,6 +23,7 @@ impl Command for Let {
                 SyntaxShape::Keyword(b"=".to_vec(), Box::new(SyntaxShape::Expression)),
                 "equals sign followed by value",
             )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/module.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Module;
@@ -22,6 +22,7 @@ impl Command for Module {
                 SyntaxShape::Block(Some(vec![])),
                 "body of the module",
             )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/register.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Register;
@@ -15,11 +15,13 @@ impl Command for Register {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("register").required(
+        Signature::build("register")
-            "plugin",
+            .required(
-            SyntaxShape::Filepath,
+                "plugin",
-            "location of bin for plugin",
+                SyntaxShape::Filepath,
-        )
+                "location of bin for plugin",
+            )
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/core_commands/source.rs

@@ -1,7 +1,7 @@
 use nu_engine::{eval_block, CallExt};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, ShellError, Signature, SyntaxShape};
 
 /// Source a file for environment variables.
 #[derive(Clone)]
@@ -13,11 +13,13 @@ impl Command for Source {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("source").required(
+        Signature::build("source")
-            "filename",
+            .required(
-            SyntaxShape::Filepath,
+                "filename",
-            "the filepath to the script file to source",
+                SyntaxShape::Filepath,
-        )
+                "the filepath to the script file to source",
+            )
+            .category(Category::Core)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/core_commands/use_.rs

@@ -1,7 +1,7 @@
 use nu_engine::eval_block;
 use nu_protocol::ast::{Call, Expr, Expression, ImportPatternMember};
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature, Span, SyntaxShape};
+use nu_protocol::{Category, PipelineData, ShellError, Signature, Span, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Use;
@@ -16,7 +16,9 @@ impl Command for Use {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("use").rest("pattern", SyntaxShape::String, "import pattern parts")
+        Signature::build("use")
+            .rest("pattern", SyntaxShape::String, "import pattern parts")
+            .category(Category::Core)
     }
 
     fn run(

crates/nu-command/src/date/command.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    IntoPipelineData, PipelineData, ShellError, Signature, Value,
+    Category, IntoPipelineData, PipelineData, ShellError, Signature, Value,
 };
 
 #[derive(Clone)]
@@ -14,7 +14,7 @@ impl Command for Date {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date")
+        Signature::build("date").category(Category::Date)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/date/format.rs

@@ -3,7 +3,7 @@ use nu_engine::CallExt;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Example, PipelineData, Signature, Span, Spanned, SyntaxShape, Value,
+    Category, Example, PipelineData, Signature, Span, Spanned, SyntaxShape, Value,
 };
 
 use super::utils::{parse_date_from_string, unsupported_input_error};
@@ -17,11 +17,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date format").required(
+        Signature::build("date format")
-            "format string",
+            .required(
-            SyntaxShape::String,
+                "format string",
-            "the desired date format",
+                SyntaxShape::String,
-        )
+                "the desired date format",
+            )
+            .category(Category::Date)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/date/humanize.rs

@@ -3,7 +3,7 @@ use chrono::{DateTime, FixedOffset, Local};
 use chrono_humanize::HumanTime;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 #[derive(Clone)]
 pub struct SubCommand;
 
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date humanize")
+        Signature::build("date humanize").category(Category::Date)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/date/list_timezone.rs

@@ -1,7 +1,7 @@
 use chrono_tz::TZ_VARIANTS;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoInterruptiblePipelineData, PipelineData, Signature, Value};
+use nu_protocol::{Category, IntoInterruptiblePipelineData, PipelineData, Signature, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -12,7 +12,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date list-timezone")
+        Signature::build("date list-timezone").category(Category::Date)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/date/now.rs

@@ -1,7 +1,7 @@
 use chrono::Local;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoPipelineData, PipelineData, Signature, Value};
+use nu_protocol::{Category, IntoPipelineData, PipelineData, Signature, Value};
 #[derive(Clone)]
 pub struct SubCommand;
 
@@ -11,7 +11,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date now")
+        Signature::build("date now").category(Category::Date)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/date/to_table.rs

@@ -2,7 +2,7 @@ use crate::date::utils::{parse_date_from_string, unsupported_input_error};
 use chrono::{DateTime, Datelike, FixedOffset, Local, Timelike};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date to-table")
+        Signature::build("date to-table").category(Category::Date)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/date/to_timezone.rs

@@ -5,7 +5,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
 };
 
 use chrono::{FixedOffset, TimeZone};
@@ -19,11 +19,9 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("date to-timezone").required(
+        Signature::build("date to-timezone")
-            "time zone",
+            .required("time zone", SyntaxShape::String, "time zone description")
-            SyntaxShape::String,
+            .category(Category::Date)
-            "time zone description",
-        )
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/env/let_env.rs

@@ -1,7 +1,7 @@
 use nu_engine::eval_expression;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct LetEnv;
@@ -23,6 +23,7 @@ impl Command for LetEnv {
                 SyntaxShape::Keyword(b"=".to_vec(), Box::new(SyntaxShape::String)),
                 "equals sign followed by value",
             )
+            .category(Category::Env)
     }
 
     fn run(

crates/nu-command/src/env/with_env.rs

@@ -7,7 +7,7 @@ use nu_engine::{eval_block, CallExt};
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Example, PipelineData, ShellError, Signature, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -30,6 +30,7 @@ impl Command for WithEnv {
                 SyntaxShape::Block(Some(vec![SyntaxShape::Any])),
                 "the block to run once the variable is set",
             )
+            .category(Category::Env)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/experimental/git.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoPipelineData, PipelineData, Signature, Value};
+use nu_protocol::{Category, IntoPipelineData, PipelineData, Signature, Value};
 
 #[derive(Clone)]
 pub struct Git;
@@ -15,7 +15,7 @@ impl Command for Git {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("git")
+        Signature::build("git").category(Category::Experimental)
     }
 
     fn run(

crates/nu-command/src/experimental/git_checkout.rs

@@ -1,7 +1,7 @@
 use nu_engine::eval_expression;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoPipelineData, PipelineData, Signature, SyntaxShape, Value};
+use nu_protocol::{Category, IntoPipelineData, PipelineData, Signature, SyntaxShape, Value};
 
 #[derive(Clone)]
 pub struct GitCheckout;
@@ -16,11 +16,13 @@ impl Command for GitCheckout {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("git checkout").required(
+        Signature::build("git checkout")
-            "branch",
+            .required(
-            SyntaxShape::Custom(Box::new(SyntaxShape::String), "list-git-branches".into()),
+                "branch",
-            "the branch to checkout",
+                SyntaxShape::Custom(Box::new(SyntaxShape::String), "list-git-branches".into()),
-        )
+                "the branch to checkout",
+            )
+            .category(Category::Experimental)
     }
 
     fn run(

crates/nu-command/src/experimental/list_git_branches.rs

@@ -7,6 +7,7 @@ use nu_protocol::ast::Call;
 use nu_protocol::engine::Command;
 use nu_protocol::engine::EngineState;
 use nu_protocol::engine::Stack;
+use nu_protocol::Category;
 use nu_protocol::IntoInterruptiblePipelineData;
 use nu_protocol::PipelineData;
 use nu_protocol::{Signature, Value};
@@ -25,7 +26,7 @@ impl Command for ListGitBranches {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("list-git-branches")
+        Signature::build("list-git-branches").category(Category::Experimental)
     }
 
     fn run(

crates/nu-command/src/filesystem/cd.rs

@@ -1,7 +1,7 @@
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Cd;
@@ -16,7 +16,9 @@ impl Command for Cd {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("cd").optional("path", SyntaxShape::Filepath, "the path to change to")
+        Signature::build("cd")
+            .optional("path", SyntaxShape::Filepath, "the path to change to")
+            .category(Category::FileSystem)
     }
 
     fn run(

crates/nu-command/src/filesystem/cp.rs

@@ -6,7 +6,7 @@ use nu_engine::CallExt;
 use nu_path::canonicalize_with;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, ShellError, Signature, SyntaxShape};
 
 use crate::filesystem::util::FileStructure;
 
@@ -34,6 +34,7 @@ impl Command for Cp {
             )
             .switch("force", "suppress error when no file", Some('f'))
             .switch("interactive", "ask user to confirm action", Some('i'))
+            .category(Category::FileSystem)
     }
 
     fn run(

crates/nu-command/src/filesystem/ls.rs

@@ -3,7 +3,9 @@ use lscolors::{LsColors, Style};
 use nu_engine::eval_expression;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoInterruptiblePipelineData, PipelineData, Signature, SyntaxShape, Value};
+use nu_protocol::{
+    Category, IntoInterruptiblePipelineData, PipelineData, Signature, SyntaxShape, Value,
+};
 
 #[derive(Clone)]
 pub struct Ls;
@@ -19,11 +21,13 @@ impl Command for Ls {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("ls").optional(
+        Signature::build("ls")
-            "pattern",
+            .optional(
-            SyntaxShape::GlobPattern,
+                "pattern",
-            "the glob pattern to use",
+                SyntaxShape::GlobPattern,
-        )
+                "the glob pattern to use",
+            )
+            .category(Category::FileSystem)
     }
 
     fn run(

crates/nu-command/src/filesystem/mkdir.rs

@@ -5,7 +5,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, SyntaxShape, Value,
+    Category, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, SyntaxShape,
+    Value,
 };
 
 #[derive(Clone)]
@@ -24,6 +25,7 @@ impl Command for Mkdir {
                 "the name(s) of the path(s) to create",
             )
             .switch("show-created-paths", "show the path(s) created.", Some('s'))
+            .category(Category::FileSystem)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filesystem/mv.rs

@@ -5,7 +5,7 @@ use super::util::get_interactive_confirmation;
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, ShellError, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Mv;
@@ -34,6 +34,7 @@ impl Command for Mv {
             )
             .switch("interactive", "ask user to confirm action", Some('i'))
             .switch("force", "suppress error when no file", Some('f'))
+            .category(Category::FileSystem)
     }
 
     fn run(

crates/nu-command/src/filesystem/rm.rs

@@ -9,7 +9,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, SyntaxShape, Value,
+    Category, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, SyntaxShape,
+    Value,
 };
 
 #[derive(Clone)]
@@ -55,6 +56,7 @@ impl Command for Rm {
                 SyntaxShape::GlobPattern,
                 "the file path(s) to remove",
             )
+            .category(Category::FileSystem)
     }
 
     fn run(

crates/nu-command/src/filesystem/touch.rs

@@ -3,7 +3,7 @@ use std::fs::OpenOptions;
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, ShellError, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Touch;
@@ -21,6 +21,7 @@ impl Command for Touch {
                 "the path of the file you want to create",
             )
             .rest("rest", SyntaxShape::Filepath, "additional files to create")
+            .category(Category::FileSystem)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/collect.rs

@@ -1,7 +1,7 @@
 use nu_engine::eval_block;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, Signature, SyntaxShape, Value};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape, Value};
 
 #[derive(Clone)]
 pub struct Collect;
@@ -12,11 +12,13 @@ impl Command for Collect {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("collect").required(
+        Signature::build("collect")
-            "block",
+            .required(
-            SyntaxShape::Block(Some(vec![SyntaxShape::Any])),
+                "block",
-            "the block to run once the stream is collected",
+                SyntaxShape::Block(Some(vec![SyntaxShape::Any])),
-        )
+                "the block to run once the stream is collected",
+            )
+            .category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/each.rs

@@ -2,8 +2,8 @@ use nu_engine::eval_block;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature, Span,
+    Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature,
-    SyntaxShape, Value,
+    Span, SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -26,6 +26,7 @@ impl Command for Each {
                 "the block to run",
             )
             .switch("numbered", "iterate with an index", Some('n'))
+            .category(Category::Filters)
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/filters/first.rs

@@ -2,7 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
+    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape,
+    Type, Value,
 };
 
 #[derive(Clone)]
@@ -14,11 +15,13 @@ impl Command for First {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("first").optional(
+        Signature::build("first")
-            "rows",
+            .optional(
-            SyntaxShape::Int,
+                "rows",
-            "starting from the front, the number of rows to return",
+                SyntaxShape::Int,
-        )
+                "starting from the front, the number of rows to return",
+            )
+            .category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/get.rs

@@ -1,7 +1,7 @@
 use nu_engine::CallExt;
 use nu_protocol::ast::{Call, CellPath};
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoPipelineData, PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, IntoPipelineData, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Get;
@@ -16,11 +16,13 @@ impl Command for Get {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("get").required(
+        Signature::build("get")
-            "cell_path",
+            .required(
-            SyntaxShape::CellPath,
+                "cell_path",
-            "the cell path to the data",
+                SyntaxShape::CellPath,
-        )
+                "the cell path to the data",
+            )
+            .category(Category::Filters)
     }
 
     fn run(

crates/nu-command/src/filters/last.rs

@@ -3,8 +3,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape,
+    Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Span,
-    Value,
+    SyntaxShape, Value,
 };
 use std::convert::TryInto;
 
@@ -17,11 +17,13 @@ impl Command for Last {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("last").optional(
+        Signature::build("last")
-            "rows",
+            .optional(
-            SyntaxShape::Int,
+                "rows",
-            "starting from the back, the number of rows to return",
+                SyntaxShape::Int,
-        )
+                "starting from the back, the number of rows to return",
+            )
+            .category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/length.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoPipelineData, PipelineData, Signature, Value};
+use nu_protocol::{Category, IntoPipelineData, PipelineData, Signature, Value};
 
 #[derive(Clone)]
 pub struct Length;
@@ -15,7 +15,7 @@ impl Command for Length {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("length")
+        Signature::build("length").category(Category::Filters)
     }
 
     fn run(

crates/nu-command/src/filters/lines.rs

@@ -1,6 +1,8 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Value};
+use nu_protocol::{
+    Category, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Value,
+};
 
 #[derive(Clone)]
 pub struct Lines;
@@ -17,7 +19,7 @@ impl Command for Lines {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("lines")
+        Signature::build("lines").category(Category::Filters)
     }
 
     fn run(

crates/nu-command/src/filters/par_each.rs

@@ -2,8 +2,8 @@ use nu_engine::eval_block;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature, SyntaxShape,
+    Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature,
-    Value,
+    SyntaxShape, Value,
 };
 use rayon::prelude::*;
 
@@ -27,6 +27,7 @@ impl Command for ParEach {
                 "the block to run",
             )
             .switch("numbered", "iterate with an index", Some('n'))
+            .category(Category::Filters)
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/filters/range.rs

@@ -3,8 +3,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape,
+    Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Span,
-    Value,
+    SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -16,11 +16,13 @@ impl Command for Range {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("range").optional(
+        Signature::build("range")
-            "rows",
+            .optional(
-            SyntaxShape::Range,
+                "rows",
-            "range of rows to return: Eg) 4..7 (=> from 4 to 7)",
+                SyntaxShape::Range,
-        )
+                "range of rows to return: Eg) 4..7 (=> from 4 to 7)",
+            )
+            .category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/reverse.rs

@@ -1,7 +1,8 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Span, Value,
+    Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Span,
+    Value,
 };
 
 #[derive(Clone)]
@@ -13,7 +14,7 @@ impl Command for Reverse {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("reverse")
+        Signature::build("reverse").category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/select.rs

@@ -2,8 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::{Call, CellPath};
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError, Signature,
+    Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError,
-    Span, SyntaxShape, Value,
+    Signature, Span, SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -15,11 +15,13 @@ impl Command for Select {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("select").rest(
+        Signature::build("select")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "the columns to select from the table",
+                SyntaxShape::CellPath,
-        )
+                "the columns to select from the table",
+            )
+            .category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/shuffle.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{IntoInterruptiblePipelineData, PipelineData, ShellError, Signature};
+use nu_protocol::{Category, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature};
 use rand::prelude::SliceRandom;
 use rand::thread_rng;
 
@@ -13,7 +13,7 @@ impl Command for Shuffle {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("shuffle")
+        Signature::build("shuffle").category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/update.rs

@@ -2,7 +2,8 @@ use nu_engine::{eval_block, CallExt};
 use nu_protocol::ast::{Call, CellPath};
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape,
+    Value,
 };
 
 #[derive(Clone)]
@@ -25,6 +26,7 @@ impl Command for Update {
                 SyntaxShape::Any,
                 "the new value to give the cell(s)",
             )
+            .category(Category::Filters)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/filters/where_.rs

@@ -1,7 +1,7 @@
 use nu_engine::eval_expression;
 use nu_protocol::ast::{Call, Expr, Expression};
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature, SyntaxShape};
+use nu_protocol::{Category, PipelineData, ShellError, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Where;
@@ -16,7 +16,9 @@ impl Command for Where {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("where").required("cond", SyntaxShape::RowCondition, "condition")
+        Signature::build("where")
+            .required("cond", SyntaxShape::RowCondition, "condition")
+            .category(Category::Filters)
     }
 
     fn run(

crates/nu-command/src/filters/wrap.rs

@@ -2,7 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature, SyntaxShape, Value,
+    Category, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature,
+    SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -18,7 +19,9 @@ impl Command for Wrap {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("wrap").required("name", SyntaxShape::String, "the name of the column")
+        Signature::build("wrap")
+            .required("name", SyntaxShape::String, "the name of the column")
+            .category(Category::Filters)
     }
 
     fn run(

crates/nu-command/src/filters/zip.rs

@@ -2,8 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature, SyntaxShape,
+    Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, Signature,
-    Value,
+    SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -19,7 +19,9 @@ impl Command for Zip {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("zip").required("other", SyntaxShape::Any, "the other input")
+        Signature::build("zip")
+            .required("other", SyntaxShape::Any, "the other input")
+            .category(Category::Filters)
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/formats/from/command.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature};
+use nu_protocol::{Category, PipelineData, ShellError, Signature};
 
 #[derive(Clone)]
 pub struct From;
@@ -15,7 +15,7 @@ impl Command for From {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("from")
+        Signature::build("from").category(Category::Formats)
     }
 
     fn run(

crates/nu-command/src/formats/from/csv.rs

@@ -3,7 +3,7 @@ use super::delimited::from_delimited_data;
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, SyntaxShape, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Value};
 
 #[derive(Clone)]
 pub struct FromCsv;
@@ -26,6 +26,7 @@ impl Command for FromCsv {
                 "don't treat the first row as column names",
                 Some('n'),
             )
+            .category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/eml.rs

@@ -4,6 +4,7 @@ use indexmap::map::IndexMap;
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::Category;
 use nu_protocol::Config;
 use nu_protocol::{
     Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
@@ -20,12 +21,14 @@ impl Command for FromEml {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from eml").named(
+        Signature::build("from eml")
-            "preview-body",
+            .named(
-            SyntaxShape::Int,
+                "preview-body",
-            "How many bytes of the body to preview",
+                SyntaxShape::Int,
-            Some('b'),
+                "How many bytes of the body to preview",
-        )
+                Some('b'),
+            )
+            .category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/json.rs

@@ -1,8 +1,8 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError, Signature,
+    Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError,
-    Span, Value,
+    Signature, Span, Value,
 };
 
 #[derive(Clone)]
@@ -18,11 +18,9 @@ impl Command for FromJson {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("from json").switch(
+        Signature::build("from json")
-            "objects",
+            .switch("objects", "treat each line as a separate value", Some('o'))
-            "treat each line as a separate value",
+            .category(Category::Formats)
-            Some('o'),
-        )
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/formats/from/tsv.rs

@@ -2,7 +2,7 @@ use super::delimited::from_delimited_data;
 
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Config, PipelineData, ShellError, Signature};
+use nu_protocol::{Category, Config, PipelineData, ShellError, Signature};
 
 #[derive(Clone)]
 pub struct FromTsv;
@@ -13,11 +13,13 @@ impl Command for FromTsv {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from csv").switch(
+        Signature::build("from csv")
-            "noheaders",
+            .switch(
-            "don't treat the first row as column names",
+                "noheaders",
-            Some('n'),
+                "don't treat the first row as column names",
-        )
+                Some('n'),
+            )
+            .category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/url.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Config, Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Config, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct FromUrl;
@@ -11,7 +11,7 @@ impl Command for FromUrl {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from url")
+        Signature::build("from url").category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/from/yaml.rs

@@ -2,7 +2,8 @@ use itertools::Itertools;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Config, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, Spanned, Value,
+    Category, Config, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span,
+    Spanned, Value,
 };
 use serde::de::Deserialize;
 use std::collections::HashMap;
@@ -16,7 +17,7 @@ impl Command for FromYaml {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from yaml")
+        Signature::build("from yaml").category(Category::Formats)
     }
 
     fn usage(&self) -> &str {
@@ -84,7 +85,7 @@ impl Command for FromYml {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("from yml")
+        Signature::build("from yml").category(Category::Formats)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/formats/to/command.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{PipelineData, ShellError, Signature};
+use nu_protocol::{Category, PipelineData, ShellError, Signature};
 
 #[derive(Clone)]
 pub struct To;
@@ -15,7 +15,7 @@ impl Command for To {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("to")
+        Signature::build("to").category(Category::Formats)
     }
 
     fn run(

crates/nu-command/src/formats/to/json.rs

@@ -1,8 +1,8 @@
 use nu_protocol::ast::{Call, PathMember};
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError, Signature,
+    Category, Example, IntoInterruptiblePipelineData, IntoPipelineData, PipelineData, ShellError,
-    Value,
+    Signature, Value,
 };
 
 #[derive(Clone)]
@@ -14,7 +14,7 @@ impl Command for ToJson {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("to json")
+        Signature::build("to json").category(Category::Formats)
         // .named(
         //     "pretty",
         //     SyntaxShape::Int,

crates/nu-command/src/math/abs.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -11,7 +11,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math abs")
+        Signature::build("math abs").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/avg.rs

@@ -2,7 +2,7 @@ use crate::math::reducers::{reducer_for, Reduce};
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math avg")
+        Signature::build("math avg").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/ceil.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -11,7 +11,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math ceil")
+        Signature::build("math ceil").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/command.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Value,
 };
 
 #[derive(Clone)]
@@ -14,7 +14,7 @@ impl Command for MathCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math")
+        Signature::build("math").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/eval.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
 };
 
 #[derive(Clone)]
@@ -18,11 +18,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math eval").optional(
+        Signature::build("math eval")
-            "math expression",
+            .optional(
-            SyntaxShape::String,
+                "math expression",
-            "the math expression to evaluate",
+                SyntaxShape::String,
-        )
+                "the math expression to evaluate",
+            )
+            .category(Category::Math)
     }
 
     fn run(

crates/nu-command/src/math/floor.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -11,7 +11,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math floor")
+        Signature::build("math floor").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/max.rs

@@ -2,7 +2,7 @@ use crate::math::reducers::{reducer_for, Reduce};
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math max")
+        Signature::build("math max").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/median.rs

@@ -2,7 +2,7 @@ use crate::math::avg::average;
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math median")
+        Signature::build("math median").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/min.rs

@@ -2,7 +2,7 @@ use crate::math::reducers::{reducer_for, Reduce};
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math min")
+        Signature::build("math min").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/mode.rs

@@ -1,7 +1,7 @@
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 use std::cmp::Ordering;
 
 #[derive(Clone)]
@@ -36,7 +36,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math mode")
+        Signature::build("math mode").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/product.rs

@@ -2,7 +2,7 @@ use crate::math::reducers::{reducer_for, Reduce};
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math product")
+        Signature::build("math product").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/round.rs

@@ -1,7 +1,9 @@
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -12,12 +14,14 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math round").named(
+        Signature::build("math round")
-            "precision",
+            .named(
-            SyntaxShape::Number,
+                "precision",
-            "digits of precision",
+                SyntaxShape::Number,
-            Some('p'),
+                "digits of precision",
-        )
+                Some('p'),
+            )
+            .category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/sqrt.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -11,7 +11,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math sqrt")
+        Signature::build("math sqrt").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/stddev.rs

@@ -2,7 +2,7 @@ use super::variance::compute_variance as variance;
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,11 +13,9 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math stddev").switch(
+        Signature::build("math stddev")
-            "sample",
+            .switch("sample", "calculate sample standard deviation", Some('s'))
-            "calculate sample standard deviation",
+            .category(Category::Math)
-            Some('s'),
-        )
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/sum.rs

@@ -2,7 +2,7 @@ use crate::math::reducers::{reducer_for, Reduce};
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math sum")
+        Signature::build("math sum").category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/math/variance.rs

@@ -1,7 +1,7 @@
 use crate::math::utils::run_with_function;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Value};
 
 #[derive(Clone)]
 pub struct SubCommand;
@@ -12,7 +12,9 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("math variance").switch("sample", "calculate sample variance", Some('s'))
+        Signature::build("math variance")
+            .switch("sample", "calculate sample variance", Some('s'))
+            .category(Category::Math)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/build_string.rs

@@ -2,7 +2,8 @@ use nu_engine::eval_expression;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape,
+    Value,
 };
 
 #[derive(Clone)]
@@ -18,7 +19,9 @@ impl Command for BuildString {
     }
 
     fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("build-string").rest("rest", SyntaxShape::String, "list of string")
+        Signature::build("build-string")
+            .rest("rest", SyntaxShape::String, "list of string")
+            .category(Category::Strings)
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/strings/format/command.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::{Call, PathMember};
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value, ValueStream,
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value, ValueStream,
 };
 
 #[derive(Clone)]
@@ -14,11 +14,13 @@ impl Command for Format {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("format").required(
+        Signature::build("format")
-            "pattern",
+            .required(
-            SyntaxShape::String,
+                "pattern",
-            "the pattern to output. e.g.) \"{foo}: {bar}\"",
+                SyntaxShape::String,
-        )
+                "the pattern to output. e.g.) \"{foo}: {bar}\"",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/parse.rs

@@ -2,8 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type,
-    ValueStream,
+    Value, ValueStream,
 };
 use regex::Regex;
 
@@ -27,6 +27,7 @@ impl Command for Parse {
                 "the pattern to match. Eg) \"{foo}: {bar}\"",
             )
             .switch("regex", "use full regex syntax for patterns", Some('r'))
+            .category(Category::Strings)
     }
 
     fn examples(&self) -> Vec<Example> {

crates/nu-command/src/strings/size.rs

@@ -4,7 +4,7 @@ use unicode_segmentation::UnicodeSegmentation;
 
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, Type, Value};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, Span, Type, Value};
 
 #[derive(Clone)]
 pub struct Size;
@@ -15,7 +15,7 @@ impl Command for Size {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("size")
+        Signature::build("size").category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/split/chars.rs

@@ -1,7 +1,7 @@
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    Example, PipelineData, ShellError, Signature, Span, Type, Value,
+    Category, Example, PipelineData, ShellError, Signature, Span, Type, Value,
 };
 
 #[derive(Clone)]
@@ -13,7 +13,7 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("split chars")
+        Signature::build("split chars").category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/split/column.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
+    Category, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
 };
 
 #[derive(Clone)]
@@ -26,6 +26,7 @@ impl Command for SubCommand {
                 SyntaxShape::String,
                 "column names to give the new columns",
             )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/split/command.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Value,
 };
 
 #[derive(Clone)]
@@ -14,7 +14,7 @@ impl Command for SplitCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("split")
+        Signature::build("split").category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/split/row.rs

@@ -2,7 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
+    Category, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Value,
 };
 
 #[derive(Clone)]
@@ -14,11 +14,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("split row").required(
+        Signature::build("split row")
-            "separator",
+            .required(
-            SyntaxShape::String,
+                "separator",
-            "the character that denotes what separates rows",
+                SyntaxShape::String,
-        )
+                "the character that denotes what separates rows",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/capitalize.rs

@@ -2,6 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::ast::CellPath;
 use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::Category;
 use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
 
 #[derive(Clone)]
@@ -13,11 +14,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str capitalize").rest(
+        Signature::build("str capitalize")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "optionally capitalize text by column paths",
+                SyntaxShape::CellPath,
-        )
+                "optionally capitalize text by column paths",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/case/camel_case.rs

@@ -1,7 +1,9 @@
 use inflector::cases::camelcase::to_camel_case;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+};
 
 use crate::operate;
 
@@ -14,11 +16,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str camel-case").rest(
+        Signature::build("str camel-case")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "optionally convert text to camelCase by column paths",
+                SyntaxShape::CellPath,
-        )
+                "optionally convert text to camelCase by column paths",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/case/command.rs

@@ -2,7 +2,7 @@ use nu_engine::get_full_help;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
-    IntoPipelineData, PipelineData, Signature, Value,
+    Category, IntoPipelineData, PipelineData, Signature, Value,
 };
 
 #[derive(Clone)]
@@ -14,7 +14,7 @@ impl Command for Str {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str")
+        Signature::build("str").category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/case/kebab_case.rs

@@ -1,7 +1,9 @@
 use inflector::cases::kebabcase::to_kebab_case;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+};
 
 use crate::operate;
 
@@ -14,11 +16,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str kebab-case").rest(
+        Signature::build("str kebab-case")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "optionally convert text to kebab-case by column paths",
+                SyntaxShape::CellPath,
-        )
+                "optionally convert text to kebab-case by column paths",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/case/pascal_case.rs

@@ -1,7 +1,9 @@
 use inflector::cases::pascalcase::to_pascal_case;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+};
 
 use crate::operate;
 
@@ -14,11 +16,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str pascal-case").rest(
+        Signature::build("str pascal-case")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "optionally convert text to PascalCase by column paths",
+                SyntaxShape::CellPath,
-        )
+                "optionally convert text to PascalCase by column paths",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/case/screaming_snake_case.rs

@@ -1,7 +1,9 @@
 use inflector::cases::screamingsnakecase::to_screaming_snake_case;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+};
 
 use crate::operate;
 #[derive(Clone)]
@@ -13,11 +15,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str screaming-snake-case").rest(
+        Signature::build("str screaming-snake-case")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "optionally convert text to SCREAMING_SNAKE_CASE by column paths",
+                SyntaxShape::CellPath,
-        )
+                "optionally convert text to SCREAMING_SNAKE_CASE by column paths",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/case/snake_case.rs

@@ -1,7 +1,9 @@
 use inflector::cases::snakecase::to_snake_case;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+};
 
 use crate::operate;
 #[derive(Clone)]
@@ -13,11 +15,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str snake-case").rest(
+        Signature::build("str snake-case")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "optionally convert text to snake_case by column paths",
+                SyntaxShape::CellPath,
-        )
+                "optionally convert text to snake_case by column paths",
+            )
+            .category(Category::Strings)
     }
     fn usage(&self) -> &str {
         "converts a string to snake_case"

crates/nu-command/src/strings/str_/collect.rs

@@ -2,7 +2,8 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
 use nu_protocol::{
-    Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape, Value,
+    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Span, SyntaxShape,
+    Value,
 };
 
 #[derive(Clone)]
@@ -14,11 +15,13 @@ impl Command for StrCollect {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str collect").optional(
+        Signature::build("str collect")
-            "separator",
+            .optional(
-            SyntaxShape::String,
+                "separator",
-            "optional separator to use when creating string",
+                SyntaxShape::String,
-        )
+                "optional separator to use when creating string",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/contains.rs

@@ -2,6 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::ast::CellPath;
 use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::Category;
 use nu_protocol::{
     Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Value,
 };
@@ -23,6 +24,7 @@ impl Command for SubCommand {
                 "optionally check if string contains pattern by column paths",
             )
             .switch("insensitive", "search is case insensitive", Some('i'))
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/downcase.rs

@@ -2,6 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::ast::CellPath;
 use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::Category;
 use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
 
 #[derive(Clone)]
@@ -13,11 +14,13 @@ impl Command for SubCommand {
     }
 
     fn signature(&self) -> Signature {
-        Signature::build("str downcase").rest(
+        Signature::build("str downcase")
-            "rest",
+            .rest(
-            SyntaxShape::CellPath,
+                "rest",
-            "optionally downcase text by column paths",
+                SyntaxShape::CellPath,
-        )
+                "optionally downcase text by column paths",
+            )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {

crates/nu-command/src/strings/str_/ends_with.rs

@@ -2,6 +2,7 @@ use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::ast::CellPath;
 use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::Category;
 use nu_protocol::Spanned;
 use nu_protocol::{Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Value};
 
@@ -21,6 +22,7 @@ impl Command for SubCommand {
                 SyntaxShape::CellPath,
                 "optionally matches suffix of text by column paths",
             )
+            .category(Category::Strings)
     }
 
     fn usage(&self) -> &str {