diff --git a/crates/nu-command/src/commands/math/abs.rs b/crates/nu-command/src/commands/math/abs.rs
index 0ed327b268..bec1cb633c 100644
--- a/crates/nu-command/src/commands/math/abs.rs
+++ b/crates/nu-command/src/commands/math/abs.rs
@@ -18,7 +18,7 @@ impl WholeStreamCommand for SubCommand {
         "Returns absolute values of a list of numbers"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let mapped = args.input.map(move |val| match val.value {
             UntaggedValue::Primitive(Primitive::Int(val)) => {
                 UntaggedValue::int(val.magnitude().clone()).into()
@@ -31,7 +31,7 @@ impl WholeStreamCommand for SubCommand {
             }
             other => abs_default(other),
         });
-        Ok(ActionStream::from_input(mapped))
+        Ok(mapped.to_output_stream())
     }
 
     fn examples(&self) -> Vec<Example> {
diff --git a/crates/nu-command/src/commands/math/avg.rs b/crates/nu-command/src/commands/math/avg.rs
index 84f46a8e4e..13f7ccd74c 100644
--- a/crates/nu-command/src/commands/math/avg.rs
+++ b/crates/nu-command/src/commands/math/avg.rs
@@ -27,7 +27,7 @@ impl WholeStreamCommand for SubCommand {
         "Finds the average of a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         run_with_function(args, average)
     }
 
diff --git a/crates/nu-command/src/commands/math/ceil.rs b/crates/nu-command/src/commands/math/ceil.rs
index 7b10387040..c981592a50 100644
--- a/crates/nu-command/src/commands/math/ceil.rs
+++ b/crates/nu-command/src/commands/math/ceil.rs
@@ -20,7 +20,7 @@ impl WholeStreamCommand for SubCommand {
         "Applies the ceil function to a list of numbers"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let input = args.input;
 
         run_with_numerical_functions_on_stream(input, ceil_big_int, ceil_big_decimal, ceil_default)
diff --git a/crates/nu-command/src/commands/math/command.rs b/crates/nu-command/src/commands/math/command.rs
index 6b8f546fca..dee791ce66 100644
--- a/crates/nu-command/src/commands/math/command.rs
+++ b/crates/nu-command/src/commands/math/command.rs
@@ -1,7 +1,7 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, Signature, UntaggedValue};
+use nu_protocol::{Signature, UntaggedValue};
 
 pub struct Command;
 
@@ -18,10 +18,10 @@ impl WholeStreamCommand for Command {
         "Use mathematical functions as aggregate functions on a list of numbers or tables."
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
-        Ok(ActionStream::one(Ok(ReturnSuccess::Value(
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
+        Ok(OutputStream::one(
             UntaggedValue::string(get_full_help(&Command, &args.scope)).into_value(Tag::unknown()),
-        ))))
+        ))
     }
 }
 
diff --git a/crates/nu-command/src/commands/math/eval.rs b/crates/nu-command/src/commands/math/eval.rs
index 9077802271..56e795f774 100644
--- a/crates/nu-command/src/commands/math/eval.rs
+++ b/crates/nu-command/src/commands/math/eval.rs
@@ -1,16 +1,11 @@
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_protocol::{Primitive, Signature, SyntaxShape, UntaggedValue, Value};
 use nu_source::Tagged;
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-pub struct SubCommandArgs {
-    expression: Option<Tagged<String>>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "math eval"
@@ -28,7 +23,7 @@ impl WholeStreamCommand for SubCommand {
         )
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         eval(args)
     }
 
@@ -45,13 +40,15 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-pub fn eval(args: CommandArgs) -> Result<ActionStream, ShellError> {
-    let name = args.call_info.name_tag.span;
-    let (SubCommandArgs { expression }, input) = args.process()?;
+pub fn eval(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once()?;
+    let expression: Option<Result<Tagged<String>, ShellError>> = args.opt(0);
+    let name = args.call_info.name_tag.clone();
+    let input = args.input;
 
-    if let Some(string) = expression {
+    if let Some(Ok(string)) = expression {
         match parse(&string, &string.tag) {
-            Ok(value) => Ok(ActionStream::one(ReturnSuccess::value(value))),
+            Ok(value) => Ok(OutputStream::one(value)),
             Err(err) => Err(ShellError::labeled_error(
                 "Math evaluation error",
                 err,
@@ -59,12 +56,12 @@ pub fn eval(args: CommandArgs) -> Result<ActionStream, ShellError> {
             )),
         }
     } else {
-        Ok(input
+        let mapped: Result<Vec<_>, _> = input
             .map(move |x| {
-                if let Some(Tagged {
+                if let Some(Ok(Tagged {
                     tag,
                     item: expression,
-                }) = &expression
+                })) = &expression
                 {
                     UntaggedValue::string(expression).into_value(tag)
                 } else {
@@ -74,7 +71,7 @@ pub fn eval(args: CommandArgs) -> Result<ActionStream, ShellError> {
             .map(move |input| {
                 if let Ok(string) = input.as_string() {
                     match parse(&string, &input.tag) {
-                        Ok(value) => ReturnSuccess::value(value),
+                        Ok(value) => Ok(value),
                         Err(err) => Err(ShellError::labeled_error(
                             "Math evaluation error",
                             err,
@@ -85,11 +82,15 @@ pub fn eval(args: CommandArgs) -> Result<ActionStream, ShellError> {
                     Err(ShellError::labeled_error(
                         "Expected a string from pipeline",
                         "requires string input",
-                        name,
+                        name.clone(),
                     ))
                 }
             })
-            .to_action_stream())
+            .collect();
+        match mapped {
+            Ok(values) => Ok(OutputStream::from(values)),
+            Err(e) => Err(e),
+        }
     }
 }
 
diff --git a/crates/nu-command/src/commands/math/floor.rs b/crates/nu-command/src/commands/math/floor.rs
index 1fa82dd6e1..d5da9f6a05 100644
--- a/crates/nu-command/src/commands/math/floor.rs
+++ b/crates/nu-command/src/commands/math/floor.rs
@@ -20,7 +20,7 @@ impl WholeStreamCommand for SubCommand {
         "Applies the floor function to a list of numbers"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         let input = args.input;
 
         run_with_numerical_functions_on_stream(
diff --git a/crates/nu-command/src/commands/math/max.rs b/crates/nu-command/src/commands/math/max.rs
index 9cd9ca3620..0facfafcc0 100644
--- a/crates/nu-command/src/commands/math/max.rs
+++ b/crates/nu-command/src/commands/math/max.rs
@@ -20,7 +20,7 @@ impl WholeStreamCommand for SubCommand {
         "Finds the maximum within a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         run_with_function(args, maximum)
     }
 
diff --git a/crates/nu-command/src/commands/math/median.rs b/crates/nu-command/src/commands/math/median.rs
index 519bdc0ff4..de7a4a9b76 100644
--- a/crates/nu-command/src/commands/math/median.rs
+++ b/crates/nu-command/src/commands/math/median.rs
@@ -24,7 +24,7 @@ impl WholeStreamCommand for SubCommand {
         "Gets the median of a list of numbers"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         run_with_function(args, median)
     }
 
diff --git a/crates/nu-command/src/commands/math/min.rs b/crates/nu-command/src/commands/math/min.rs
index c747700adf..2ed64a0c44 100644
--- a/crates/nu-command/src/commands/math/min.rs
+++ b/crates/nu-command/src/commands/math/min.rs
@@ -20,7 +20,7 @@ impl WholeStreamCommand for SubCommand {
         "Finds the minimum within a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         run_with_function(args, minimum)
     }
 
diff --git a/crates/nu-command/src/commands/math/mode.rs b/crates/nu-command/src/commands/math/mode.rs
index 932e6ed202..112808ebf2 100644
--- a/crates/nu-command/src/commands/math/mode.rs
+++ b/crates/nu-command/src/commands/math/mode.rs
@@ -20,7 +20,7 @@ impl WholeStreamCommand for SubCommand {
         "Gets the most frequent element(s) from a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         run_with_function(args, mode)
     }
 
diff --git a/crates/nu-command/src/commands/math/product.rs b/crates/nu-command/src/commands/math/product.rs
index 8c36f38b49..62decd9ba4 100644
--- a/crates/nu-command/src/commands/math/product.rs
+++ b/crates/nu-command/src/commands/math/product.rs
@@ -20,7 +20,7 @@ impl WholeStreamCommand for SubCommand {
         "Finds the product of a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         run_with_function(args, product)
     }
 
diff --git a/crates/nu-command/src/commands/math/round.rs b/crates/nu-command/src/commands/math/round.rs
index 60910b77eb..b10f6d07c0 100644
--- a/crates/nu-command/src/commands/math/round.rs
+++ b/crates/nu-command/src/commands/math/round.rs
@@ -6,11 +6,6 @@ use nu_source::Tagged;
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-struct Arguments {
-    precision: Option<Tagged<i64>>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "math round"
@@ -29,7 +24,7 @@ impl WholeStreamCommand for SubCommand {
         "Applies the round function to a list of numbers"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         operate(args)
     }
 
@@ -57,16 +52,23 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-fn operate(args: CommandArgs) -> Result<ActionStream, ShellError> {
-    let (Arguments { precision }, input) = args.process()?;
-    let precision = precision.map(|p| p.item).unwrap_or(0);
-
+fn operate(args: CommandArgs) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once()?;
+    let precision: Option<Result<Tagged<i16>, ShellError>> = args.get_flag("precision");
+    let input = args.input;
+    let precision = if let Some(precision) = precision {
+        precision?.item
+    } else {
+        0
+    };
     let mapped = input.map(move |val| match val.value {
         UntaggedValue::Primitive(Primitive::Int(val)) => round_big_int(val),
-        UntaggedValue::Primitive(Primitive::Decimal(val)) => round_big_decimal(val, precision),
+        UntaggedValue::Primitive(Primitive::Decimal(val)) => {
+            round_big_decimal(val, precision.into())
+        }
         other => round_default(other),
     });
-    Ok(ActionStream::from_input(mapped))
+    Ok(mapped.to_output_stream())
 }
 
 fn round_big_int(val: BigInt) -> Value {
diff --git a/crates/nu-command/src/commands/math/sqrt.rs b/crates/nu-command/src/commands/math/sqrt.rs
index a02ba1647d..92449a3b0b 100644
--- a/crates/nu-command/src/commands/math/sqrt.rs
+++ b/crates/nu-command/src/commands/math/sqrt.rs
@@ -18,7 +18,7 @@ impl WholeStreamCommand for SubCommand {
         "Applies the square root function to a list of numbers"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         Ok(operate(args))
     }
 
@@ -34,13 +34,13 @@ impl WholeStreamCommand for SubCommand {
     }
 }
 
-fn operate(args: CommandArgs) -> ActionStream {
+fn operate(args: CommandArgs) -> OutputStream {
     let mapped = args.input.map(move |val| match val.value {
         UntaggedValue::Primitive(Primitive::Int(val)) => sqrt_big_decimal(BigDecimal::from(val)),
         UntaggedValue::Primitive(Primitive::Decimal(val)) => sqrt_big_decimal(val),
         other => sqrt_default(other),
     });
-    ActionStream::from_input(mapped)
+    mapped.to_output_stream()
 }
 
 fn sqrt_big_decimal(val: BigDecimal) -> Value {
diff --git a/crates/nu-command/src/commands/math/stddev.rs b/crates/nu-command/src/commands/math/stddev.rs
index 3ad5e05989..c979f7d70a 100644
--- a/crates/nu-command/src/commands/math/stddev.rs
+++ b/crates/nu-command/src/commands/math/stddev.rs
@@ -2,17 +2,11 @@ use super::variance::compute_variance as variance;
 use crate::prelude::*;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{Dictionary, Primitive, ReturnSuccess, Signature, UntaggedValue, Value};
-use nu_source::Tagged;
+use nu_protocol::{Dictionary, Primitive, Signature, UntaggedValue, Value};
 use std::str::FromStr;
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-struct Arguments {
-    sample: Tagged<bool>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "math stddev"
@@ -30,13 +24,14 @@ impl WholeStreamCommand for SubCommand {
         "Finds the stddev of a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
+        let mut args = raw_args.evaluate_once()?;
+
+        let sample: bool = args.has_flag("sample");
+        let values: Vec<Value> = args.input.drain_vec();
         let name = args.call_info.name_tag.clone();
-        let (Arguments { sample }, mut input) = args.process()?;
 
-        let values: Vec<Value> = input.drain_vec();
-
-        let n = if let Tagged { item: true, .. } = sample {
+        let n = if sample {
             values.len() - 1
         } else {
             values.len()
@@ -81,13 +76,11 @@ impl WholeStreamCommand for SubCommand {
         }?;
 
         if res.value.is_table() {
-            Ok(ActionStream::from(
-                res.table_entries()
-                    .map(|v| ReturnSuccess::value(v.clone()))
-                    .collect::<Vec<_>>(),
+            Ok(OutputStream::from(
+                res.table_entries().cloned().collect::<Vec<_>>(),
             ))
         } else {
-            Ok(ActionStream::one(ReturnSuccess::value(res)))
+            Ok(OutputStream::one(res))
         }
     }
 
diff --git a/crates/nu-command/src/commands/math/sum.rs b/crates/nu-command/src/commands/math/sum.rs
index 224685e3c0..0f09a19831 100644
--- a/crates/nu-command/src/commands/math/sum.rs
+++ b/crates/nu-command/src/commands/math/sum.rs
@@ -21,7 +21,7 @@ impl WholeStreamCommand for SubCommand {
         "Finds the sum of a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, args: CommandArgs) -> Result<OutputStream, ShellError> {
         run_with_function(args, summation)
     }
 
diff --git a/crates/nu-command/src/commands/math/utils.rs b/crates/nu-command/src/commands/math/utils.rs
index fb4cd5d2d5..49378a6622 100644
--- a/crates/nu-command/src/commands/math/utils.rs
+++ b/crates/nu-command/src/commands/math/utils.rs
@@ -1,6 +1,6 @@
 use crate::prelude::*;
 use nu_errors::ShellError;
-use nu_protocol::{Dictionary, Primitive, ReturnSuccess, UntaggedValue, Value};
+use nu_protocol::{Dictionary, Primitive, UntaggedValue, Value};
 
 use indexmap::map::IndexMap;
 
@@ -9,7 +9,7 @@ pub type MathFunction = fn(values: &[Value], tag: &Tag) -> Result<Value, ShellEr
 pub fn run_with_function(
     args: impl Into<RunnableContext>,
     mf: MathFunction,
-) -> Result<ActionStream, ShellError> {
+) -> Result<OutputStream, ShellError> {
     let RunnableContext {
         mut input,
         call_info,
@@ -23,13 +23,11 @@ pub fn run_with_function(
     match res {
         Ok(v) => {
             if v.value.is_table() {
-                Ok(ActionStream::from(
-                    v.table_entries()
-                        .map(|v| ReturnSuccess::value(v.clone()))
-                        .collect::<Vec<_>>(),
+                Ok(OutputStream::from(
+                    v.table_entries().cloned().collect::<Vec<_>>(),
                 ))
             } else {
-                Ok(ActionStream::one(ReturnSuccess::value(v)))
+                Ok(OutputStream::one(v))
             }
         }
         Err(e) => Err(e),
@@ -47,13 +45,13 @@ pub fn run_with_numerical_functions_on_stream(
     int_function: IntFunction,
     decimal_function: DecimalFunction,
     default_function: DefaultFunction,
-) -> Result<ActionStream, ShellError> {
+) -> Result<OutputStream, ShellError> {
     let mapped = input.map(move |val| match val.value {
         UntaggedValue::Primitive(Primitive::Int(val)) => int_function(val),
         UntaggedValue::Primitive(Primitive::Decimal(val)) => decimal_function(val),
         other => default_function(other),
     });
-    Ok(ActionStream::from_input(mapped))
+    Ok(mapped.to_output_stream())
 }
 
 pub fn calculate(values: &[Value], name: &Tag, mf: MathFunction) -> Result<Value, ShellError> {
diff --git a/crates/nu-command/src/commands/math/variance.rs b/crates/nu-command/src/commands/math/variance.rs
index dc06e646d6..7e991420d3 100644
--- a/crates/nu-command/src/commands/math/variance.rs
+++ b/crates/nu-command/src/commands/math/variance.rs
@@ -3,18 +3,10 @@ use bigdecimal::FromPrimitive;
 use nu_data::value::compute_values;
 use nu_engine::WholeStreamCommand;
 use nu_errors::ShellError;
-use nu_protocol::{
-    hir::Operator, Dictionary, Primitive, ReturnSuccess, Signature, UntaggedValue, Value,
-};
-use nu_source::Tagged;
+use nu_protocol::{hir::Operator, Dictionary, Primitive, Signature, UntaggedValue, Value};
 
 pub struct SubCommand;
 
-#[derive(Deserialize)]
-struct Arguments {
-    sample: Tagged<bool>,
-}
-
 impl WholeStreamCommand for SubCommand {
     fn name(&self) -> &str {
         "math variance"
@@ -28,13 +20,14 @@ impl WholeStreamCommand for SubCommand {
         "Finds the variance of a list of numbers or tables"
     }
 
-    fn run_with_actions(&self, args: CommandArgs) -> Result<ActionStream, ShellError> {
+    fn run(&self, raw_args: CommandArgs) -> Result<OutputStream, ShellError> {
+        let mut args = raw_args.evaluate_once()?;
+
+        let sample: bool = args.has_flag("sample");
+        let values: Vec<Value> = args.input.drain_vec();
         let name = args.call_info.name_tag.clone();
-        let (Arguments { sample }, mut input) = args.process()?;
 
-        let values: Vec<Value> = input.drain_vec();
-
-        let n = if let Tagged { item: true, .. } = sample {
+        let n = if sample {
             values.len() - 1
         } else {
             values.len()
@@ -79,13 +72,11 @@ impl WholeStreamCommand for SubCommand {
         }?;
 
         if res.value.is_table() {
-            Ok(ActionStream::from(
-                res.table_entries()
-                    .map(|v| ReturnSuccess::value(v.clone()))
-                    .collect::<Vec<_>>(),
+            Ok(OutputStream::from(
+                res.table_entries().cloned().collect::<Vec<_>>(),
             ))
         } else {
-            Ok(ActionStream::one(ReturnSuccess::value(res)))
+            Ok(OutputStream::one(res))
         }
     }