uv tool run error messages references uvx when appropriate (#5014)

## Summary

Resolves #5013. 

## Test Plan

```console
❯ ./target/debug/uv tool run fastapi-cli
warning: `uv tool run` is experimental and may change without warning.
Resolved 9 packages in 28ms
The executable fastapi-cli was not found.
However, the following executables are available via uv tool run --from fastapi-cli <EXECUTABLE>:
- fastapi
```

```console
❯ ./target/debug/uvx fastapi-cli
warning: `uvx` is experimental and may change without warning.
Resolved 9 packages in 23ms
The executable fastapi-cli was not found.
However, the following executables are available via uvx --from fastapi-cli <EXECUTABLE>:
- fastapi
```

---------

Co-authored-by: Zanie Blue <contact@zanie.dev>

crates/uv/src/commands/mod.rs

@@ -36,6 +36,7 @@ pub(crate) use tool::dir::dir as tool_dir;
 pub(crate) use tool::install::install as tool_install;
 pub(crate) use tool::list::list as tool_list;
 pub(crate) use tool::run::run as tool_run;
+pub(crate) use tool::run::ToolRunCommand;
 pub(crate) use tool::uninstall::uninstall as tool_uninstall;
 use uv_cache::Cache;
 use uv_fs::Simplified;

crates/uv/src/commands/tool/run.rs

@@ -1,8 +1,8 @@
-use std::borrow::Cow;
 use std::ffi::OsString;
 use std::fmt::Write;
 use std::path::PathBuf;
 use std::str::FromStr;
+use std::{borrow::Cow, fmt::Display};
 
 use anyhow::{bail, Context, Result};
 use itertools::Itertools;
@@ -32,6 +32,23 @@ use crate::commands::{ExitStatus, SharedState};
 use crate::printer::Printer;
 use crate::settings::ResolverInstallerSettings;
 
+/// The user-facing command used to invoke a tool run.
+pub(crate) enum ToolRunCommand {
+    /// via the `uvx` alias
+    Uvx,
+    /// via `uv tool run`
+    ToolRun,
+}
+
+impl Display for ToolRunCommand {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            ToolRunCommand::Uvx => write!(f, "uvx"),
+            ToolRunCommand::ToolRun => write!(f, "uv tool run"),
+        }
+    }
+}
+
 /// Run a command.
 pub(crate) async fn run(
     command: ExternalCommand,
@@ -39,6 +56,7 @@ pub(crate) async fn run(
     with: Vec<String>,
     python: Option<String>,
     settings: ResolverInstallerSettings,
+    invocation_source: ToolRunCommand,
     isolated: bool,
     preview: PreviewMode,
     python_preference: PythonPreference,
@@ -50,7 +68,7 @@ pub(crate) async fn run(
     printer: Printer,
 ) -> Result<ExitStatus> {
     if preview.is_disabled() {
-        warn_user_once!("`uv tool run` is experimental and may change without warning.");
+        warn_user_once!("`{invocation_source}` is experimental and may change without warning.");
     }
 
     let has_from = from.is_some();
@@ -144,7 +162,7 @@ pub(crate) async fn run(
                                 "However, the following executables are available:",
                             )?;
                         } else {
-                            let command = format!("uv tool run --from {from} <EXECUTABLE>");
+                            let command = format!("{invocation_source} --from {from} <EXECUTABLE>");
                             writeln!(
                                 printer.stdout(),
                                 "However, the following executables are available via {}:",

crates/uv/src/lib.rs

@@ -26,7 +26,7 @@ use uv_distribution::Workspace;
 use uv_requirements::RequirementsSource;
 use uv_settings::{Combine, FilesystemOptions};
 
-use crate::commands::ExitStatus;
+use crate::commands::{ExitStatus, ToolRunCommand};
 use crate::printer::Printer;
 use crate::settings::{
     CacheSettings, GlobalSettings, PipCheckSettings, PipCompileSettings, PipFreezeSettings,
@@ -598,21 +598,28 @@ async fn run(cli: Cli) -> Result<ExitStatus> {
             Ok(ExitStatus::Success)
         }
         Commands::Tool(ToolNamespace {
-            command: ToolCommand::Run(args) | ToolCommand::Uvx(args),
+            command: run_variant @ (ToolCommand::Uvx(_) | ToolCommand::Run(_)),
         }) => {
+            let (args, invocation_source) = match run_variant {
+                ToolCommand::Uvx(args) => (args, ToolRunCommand::Uvx),
+                ToolCommand::Run(args) => (args, ToolRunCommand::ToolRun),
+                // OK guarded by the outer match statement
+                _ => unreachable!(),
+            };
+
             // Resolve the settings from the command-line arguments and workspace configuration.
             let args = settings::ToolRunSettings::resolve(args, filesystem);
             show_settings!(args);
 
             // Initialize the cache.
             let cache = cache.init()?.with_refresh(args.refresh);
-
             commands::tool_run(
                 args.command,
                 args.from,
                 args.with,
                 args.python,
                 args.settings,
+                invocation_source,
                 globals.isolated,
                 globals.preview,
                 globals.python_preference,