diff --git a/crates/nu-engine/src/documentation.rs b/crates/nu-engine/src/documentation.rs
index 370b00e3f9..9d7ea7f8f2 100644
--- a/crates/nu-engine/src/documentation.rs
+++ b/crates/nu-engine/src/documentation.rs
@@ -25,7 +25,9 @@ pub fn get_full_help(
     // execution.
     let stack = &mut stack.start_capture();
 
-    let signature = command.signature().update_from_command(command);
+    let signature = engine_state
+        .get_signature(command)
+        .update_from_command(command);
 
     get_documentation(
         &signature,
diff --git a/crates/nu-parser/src/parser.rs b/crates/nu-parser/src/parser.rs
index 33ecdadd3a..b9147ed7f9 100644
--- a/crates/nu-parser/src/parser.rs
+++ b/crates/nu-parser/src/parser.rs
@@ -949,7 +949,7 @@ pub fn parse_internal_call(
     let _ = working_set.add_span(call.head);
 
     let decl = working_set.get_decl(decl_id);
-    let signature = decl.signature();
+    let signature = working_set.get_signature(decl);
     let output = signature.get_output_type();
 
     // storing the var ID for later due to borrowing issues
diff --git a/crates/nu-protocol/src/engine/state_working_set.rs b/crates/nu-protocol/src/engine/state_working_set.rs
index 2ffcfa023b..eb60f9df8b 100644
--- a/crates/nu-protocol/src/engine/state_working_set.rs
+++ b/crates/nu-protocol/src/engine/state_working_set.rs
@@ -5,7 +5,7 @@ use crate::{
         StateDelta, Variable, VirtualPath, Visibility,
     },
     BlockId, Category, CompileError, Config, DeclId, FileId, GetSpan, Module, ModuleId, ParseError,
-    ParseWarning, Span, SpanId, Type, Value, VarId, VirtualPathId,
+    ParseWarning, Signature, Span, SpanId, Type, Value, VarId, VirtualPathId,
 };
 use core::panic;
 use std::{
@@ -710,6 +710,14 @@ impl<'a> StateWorkingSet<'a> {
         }
     }
 
+    pub fn get_signature(&self, decl: &dyn Command) -> Signature {
+        if let Some(block_id) = decl.block_id() {
+            *self.get_block(block_id).signature.clone()
+        } else {
+            decl.signature()
+        }
+    }
+
     pub fn find_commands_by_predicate(
         &self,
         predicate: impl Fn(&[u8]) -> bool,
diff --git a/tests/shell/mod.rs b/tests/shell/mod.rs
index 62f79a59c1..bedfe8304e 100644
--- a/tests/shell/mod.rs
+++ b/tests/shell/mod.rs
@@ -334,3 +334,69 @@ fn source_empty_file() {
         assert!(actual.out.is_empty());
     })
 }
+
+#[test]
+fn main_script_help_uses_script_name1() {
+    // Note: this test is somewhat fragile and might need to be adapted if the usage help message changes
+    Playground::setup("main_filename", |dirs, sandbox| {
+        sandbox.mkdir("main_filename");
+        sandbox.with_files(&[FileWithContent(
+            "script.nu",
+            r#"def main [] {}
+            "#,
+        )]);
+        let actual = nu!(cwd: dirs.test(), pipeline("nu script.nu --help"));
+        assert!(actual.out.contains("> script.nu"));
+        assert!(!actual.out.contains("> main"));
+    })
+}
+
+#[test]
+fn main_script_help_uses_script_name2() {
+    // Note: this test is somewhat fragile and might need to be adapted if the usage help message changes
+    Playground::setup("main_filename", |dirs, sandbox| {
+        sandbox.mkdir("main_filename");
+        sandbox.with_files(&[FileWithContent(
+            "script.nu",
+            r#"def main [foo: string] {}
+            "#,
+        )]);
+        let actual = nu!(cwd: dirs.test(), pipeline("nu script.nu"));
+        assert!(actual.err.contains("Usage: script.nu"));
+        assert!(!actual.err.contains("Usage: main"));
+    })
+}
+
+#[test]
+fn main_script_subcommand_help_uses_script_name1() {
+    // Note: this test is somewhat fragile and might need to be adapted if the usage help message changes
+    Playground::setup("main_filename", |dirs, sandbox| {
+        sandbox.mkdir("main_filename");
+        sandbox.with_files(&[FileWithContent(
+            "script.nu",
+            r#"def main [] {}
+            def 'main foo' [] {}
+            "#,
+        )]);
+        let actual = nu!(cwd: dirs.test(), pipeline("nu script.nu foo --help"));
+        assert!(actual.out.contains("> script.nu foo"));
+        assert!(!actual.out.contains("> main foo"));
+    })
+}
+
+#[test]
+fn main_script_subcommand_help_uses_script_name2() {
+    // Note: this test is somewhat fragile and might need to be adapted if the usage help message changes
+    Playground::setup("main_filename", |dirs, sandbox| {
+        sandbox.mkdir("main_filename");
+        sandbox.with_files(&[FileWithContent(
+            "script.nu",
+            r#"def main [] {}
+            def 'main foo' [bar: string] {}
+            "#,
+        )]);
+        let actual = nu!(cwd: dirs.test(), pipeline("nu script.nu foo"));
+        assert!(actual.err.contains("Usage: script.nu foo"));
+        assert!(!actual.err.contains("Usage: main foo"));
+    })
+}