diff --git a/crates/distribution-types/src/diagnostic.rs b/crates/distribution-types/src/diagnostic.rs
new file mode 100644
index 000000000..177dcd03c
--- /dev/null
+++ b/crates/distribution-types/src/diagnostic.rs
@@ -0,0 +1,9 @@
+use uv_normalize::PackageName;
+
+pub trait Diagnostic {
+    /// Convert the diagnostic into a user-facing message.
+    fn message(&self) -> String;
+
+    /// Returns `true` if the [`PackageName`] is involved in this diagnostic.
+    fn includes(&self, name: &PackageName) -> bool;
+}
diff --git a/crates/distribution-types/src/lib.rs b/crates/distribution-types/src/lib.rs
index cf072ff6c..cc9025ac5 100644
--- a/crates/distribution-types/src/lib.rs
+++ b/crates/distribution-types/src/lib.rs
@@ -49,6 +49,7 @@ pub use crate::annotation::*;
 pub use crate::any::*;
 pub use crate::buildable::*;
 pub use crate::cached::*;
+pub use crate::diagnostic::*;
 pub use crate::editable::*;
 pub use crate::error::*;
 pub use crate::file::*;
@@ -68,6 +69,7 @@ mod annotation;
 mod any;
 mod buildable;
 mod cached;
+mod diagnostic;
 mod editable;
 mod error;
 mod file;
diff --git a/crates/distribution-types/src/resolution.rs b/crates/distribution-types/src/resolution.rs
index a590054e4..463a5f4d9 100644
--- a/crates/distribution-types/src/resolution.rs
+++ b/crates/distribution-types/src/resolution.rs
@@ -4,22 +4,22 @@ use pep508_rs::VerbatimUrl;
 use uv_normalize::{ExtraName, PackageName};
 
 use crate::{
-    BuiltDist, DirectorySourceDist, Dist, InstalledDirectUrlDist, InstalledDist, LocalEditable,
-    Name, Requirement, RequirementSource, ResolvedDist, SourceDist,
+    BuiltDist, Diagnostic, DirectorySourceDist, Dist, InstalledDirectUrlDist, InstalledDist,
+    LocalEditable, Name, Requirement, RequirementSource, ResolvedDist, SourceDist,
 };
 
 /// A set of packages pinned at specific versions.
 #[derive(Debug, Default, Clone)]
 pub struct Resolution {
     packages: BTreeMap<PackageName, ResolvedDist>,
-    diagnostics: Vec<Diagnostic>,
+    diagnostics: Vec<ResolutionDiagnostic>,
 }
 
 impl Resolution {
     /// Create a new resolution from the given pinned packages.
     pub fn new(
         packages: BTreeMap<PackageName, ResolvedDist>,
-        diagnostics: Vec<Diagnostic>,
+        diagnostics: Vec<ResolutionDiagnostic>,
     ) -> Self {
         Self {
             packages,
@@ -63,8 +63,8 @@ impl Resolution {
         self.packages.values().map(Requirement::from)
     }
 
-    /// Return the [`Diagnostic`]s that were produced during resolution.
-    pub fn diagnostics(&self) -> &[Diagnostic] {
+    /// Return the [`ResolutionDiagnostic`]s that were produced during resolution.
+    pub fn diagnostics(&self) -> &[ResolutionDiagnostic] {
         &self.diagnostics
     }
 
@@ -99,7 +99,7 @@ impl Resolution {
 }
 
 #[derive(Debug, Clone)]
-pub enum Diagnostic {
+pub enum ResolutionDiagnostic {
     MissingExtra {
         /// The distribution that was requested with a non-existent extra. For example,
         /// `black==23.10.0`.
@@ -115,9 +115,9 @@ pub enum Diagnostic {
     },
 }
 
-impl Diagnostic {
+impl Diagnostic for ResolutionDiagnostic {
     /// Convert the diagnostic into a user-facing message.
-    pub fn message(&self) -> String {
+    fn message(&self) -> String {
         match self {
             Self::MissingExtra { dist, extra } => {
                 format!("The package `{dist}` does not have an extra named `{extra}`.")
@@ -133,7 +133,7 @@ impl Diagnostic {
     }
 
     /// Returns `true` if the [`PackageName`] is involved in this diagnostic.
-    pub fn includes(&self, name: &PackageName) -> bool {
+    fn includes(&self, name: &PackageName) -> bool {
         match self {
             Self::MissingExtra { dist, .. } => name == dist.name(),
             Self::YankedVersion { dist, .. } => name == dist.name(),
diff --git a/crates/uv-installer/src/lib.rs b/crates/uv-installer/src/lib.rs
index e4fe8e8ca..effa69ca9 100644
--- a/crates/uv-installer/src/lib.rs
+++ b/crates/uv-installer/src/lib.rs
@@ -3,7 +3,7 @@ pub use downloader::{Downloader, Reporter as DownloadReporter};
 pub use editable::{is_dynamic, BuiltEditable, InstalledEditable, ResolvedEditable};
 pub use installer::{Installer, Reporter as InstallReporter};
 pub use plan::{Plan, Planner};
-pub use site_packages::{Diagnostic, SatisfiesResult, SitePackages};
+pub use site_packages::{SatisfiesResult, SitePackages, SitePackagesDiagnostic};
 pub use uninstall::{uninstall, UninstallError};
 
 mod compile;
diff --git a/crates/uv-installer/src/site_packages.rs b/crates/uv-installer/src/site_packages.rs
index d33edfbcd..38e4db8ee 100644
--- a/crates/uv-installer/src/site_packages.rs
+++ b/crates/uv-installer/src/site_packages.rs
@@ -8,7 +8,8 @@ use rustc_hash::{FxHashMap, FxHashSet};
 use url::Url;
 
 use distribution_types::{
-    InstalledDist, Name, Requirement, UnresolvedRequirement, UnresolvedRequirementSpecification,
+    Diagnostic, InstalledDist, Name, Requirement, UnresolvedRequirement,
+    UnresolvedRequirementSpecification,
 };
 use pep440_rs::{Version, VersionSpecifiers};
 use requirements_txt::EditableRequirement;
@@ -188,7 +189,7 @@ impl SitePackages {
     }
 
     /// Validate the installed packages in the virtual environment.
-    pub fn diagnostics(&self) -> Result<Vec<Diagnostic>> {
+    pub fn diagnostics(&self) -> Result<Vec<SitePackagesDiagnostic>> {
         let mut diagnostics = Vec::new();
 
         for (package, indexes) in &self.by_name {
@@ -201,7 +202,7 @@ impl SitePackages {
 
             if let Some(conflict) = distributions.next() {
                 // There are multiple installed distributions for the same package.
-                diagnostics.push(Diagnostic::DuplicatePackage {
+                diagnostics.push(SitePackagesDiagnostic::DuplicatePackage {
                     package: package.clone(),
                     paths: std::iter::once(distribution.path().to_owned())
                         .chain(std::iter::once(conflict.path().to_owned()))
@@ -218,7 +219,7 @@ impl SitePackages {
 
                 // Determine the dependencies for the given package.
                 let Ok(metadata) = distribution.metadata() else {
-                    diagnostics.push(Diagnostic::IncompletePackage {
+                    diagnostics.push(SitePackagesDiagnostic::IncompletePackage {
                         package: package.clone(),
                         path: distribution.path().to_owned(),
                     });
@@ -228,7 +229,7 @@ impl SitePackages {
                 // Verify that the package is compatible with the current Python version.
                 if let Some(requires_python) = metadata.requires_python.as_ref() {
                     if !requires_python.contains(self.venv.interpreter().python_version()) {
-                        diagnostics.push(Diagnostic::IncompatiblePythonVersion {
+                        diagnostics.push(SitePackagesDiagnostic::IncompatiblePythonVersion {
                             package: package.clone(),
                             version: self.venv.interpreter().python_version().clone(),
                             requires_python: requires_python.clone(),
@@ -246,7 +247,7 @@ impl SitePackages {
                     match installed.as_slice() {
                         [] => {
                             // No version installed.
-                            diagnostics.push(Diagnostic::MissingDependency {
+                            diagnostics.push(SitePackagesDiagnostic::MissingDependency {
                                 package: package.clone(),
                                 requirement: dependency.clone(),
                             });
@@ -261,11 +262,13 @@ impl SitePackages {
                                 )) => {
                                     // The installed version doesn't satisfy the requirement.
                                     if !version_specifier.contains(installed.version()) {
-                                        diagnostics.push(Diagnostic::IncompatibleDependency {
-                                            package: package.clone(),
-                                            version: installed.version().clone(),
-                                            requirement: dependency.clone(),
-                                        });
+                                        diagnostics.push(
+                                            SitePackagesDiagnostic::IncompatibleDependency {
+                                                package: package.clone(),
+                                                version: installed.version().clone(),
+                                                requirement: dependency.clone(),
+                                            },
+                                        );
                                     }
                                 }
                             }
@@ -449,7 +452,7 @@ impl IntoIterator for SitePackages {
 }
 
 #[derive(Debug)]
-pub enum Diagnostic {
+pub enum SitePackagesDiagnostic {
     IncompletePackage {
         /// The package that is missing metadata.
         package: PackageName,
@@ -486,9 +489,9 @@ pub enum Diagnostic {
     },
 }
 
-impl Diagnostic {
+impl Diagnostic for SitePackagesDiagnostic {
     /// Convert the diagnostic into a user-facing message.
-    pub fn message(&self) -> String {
+    fn message(&self) -> String {
         match self {
             Self::IncompletePackage { package, path } => format!(
                 "The package `{package}` is broken or incomplete (unable to read `METADATA`). Consider recreating the virtualenv, or removing the package directory at: {}.", path.display(),
@@ -525,7 +528,7 @@ impl Diagnostic {
     }
 
     /// Returns `true` if the [`PackageName`] is involved in this diagnostic.
-    pub fn includes(&self, name: &PackageName) -> bool {
+    fn includes(&self, name: &PackageName) -> bool {
         match self {
             Self::IncompletePackage { package, .. } => name == package,
             Self::IncompatiblePythonVersion { package, .. } => name == package,
diff --git a/crates/uv-resolver/src/resolution/graph.rs b/crates/uv-resolver/src/resolution/graph.rs
index ce7d7c0d7..c40aba193 100644
--- a/crates/uv-resolver/src/resolution/graph.rs
+++ b/crates/uv-resolver/src/resolution/graph.rs
@@ -7,8 +7,8 @@ use pubgrub::type_aliases::SelectedDependencies;
 use rustc_hash::{FxHashMap, FxHashSet};
 
 use distribution_types::{
-    Diagnostic, Dist, DistributionMetadata, Name, ParsedUrlError, Requirement, ResolvedDist,
-    VersionId, VersionOrUrlRef,
+    Dist, DistributionMetadata, Name, ParsedUrlError, Requirement, ResolutionDiagnostic,
+    ResolvedDist, VersionId, VersionOrUrlRef,
 };
 use pep440_rs::{Version, VersionSpecifier};
 use pep508_rs::MarkerEnvironment;
@@ -37,7 +37,7 @@ pub struct ResolutionGraph {
     /// The set of editable requirements in this resolution.
     pub(crate) editables: Editables,
     /// Any diagnostics that were encountered while building the graph.
-    pub(crate) diagnostics: Vec<Diagnostic>,
+    pub(crate) diagnostics: Vec<ResolutionDiagnostic>,
 }
 
 impl ResolutionGraph {
@@ -90,7 +90,7 @@ impl ResolutionGraph {
                             .unwrap_or_else(|| panic!("Every package should be pinned: {name:?}"))
                             .clone();
 
-                        diagnostics.push(Diagnostic::MissingExtra {
+                        diagnostics.push(ResolutionDiagnostic::MissingExtra {
                             dist,
                             extra: extra.clone(),
                         });
@@ -111,7 +111,7 @@ impl ResolutionGraph {
                         } else {
                             let dist = Dist::from_editable(name.clone(), editable.built.clone())?;
 
-                            diagnostics.push(Diagnostic::MissingExtra {
+                            diagnostics.push(ResolutionDiagnostic::MissingExtra {
                                 dist: dist.into(),
                                 extra: extra.clone(),
                             });
@@ -141,7 +141,7 @@ impl ResolutionGraph {
                         } else {
                             let dist = Dist::from_url(name.clone(), url_to_precise(url.clone()))?;
 
-                            diagnostics.push(Diagnostic::MissingExtra {
+                            diagnostics.push(ResolutionDiagnostic::MissingExtra {
                                 dist: dist.into(),
                                 extra: extra.clone(),
                             });
@@ -177,13 +177,13 @@ impl ResolutionGraph {
                     match dist.yanked() {
                         None | Some(Yanked::Bool(false)) => {}
                         Some(Yanked::Bool(true)) => {
-                            diagnostics.push(Diagnostic::YankedVersion {
+                            diagnostics.push(ResolutionDiagnostic::YankedVersion {
                                 dist: dist.clone(),
                                 reason: None,
                             });
                         }
                         Some(Yanked::Reason(reason)) => {
-                            diagnostics.push(Diagnostic::YankedVersion {
+                            diagnostics.push(ResolutionDiagnostic::YankedVersion {
                                 dist: dist.clone(),
                                 reason: Some(reason.clone()),
                             });
@@ -411,8 +411,8 @@ impl ResolutionGraph {
             .map(|node| node.weight.dist)
     }
 
-    /// Return the [`Diagnostic`]s that were encountered while building the graph.
-    pub fn diagnostics(&self) -> &[Diagnostic] {
+    /// Return the [`ResolutionDiagnostic`]s that were encountered while building the graph.
+    pub fn diagnostics(&self) -> &[ResolutionDiagnostic] {
         &self.diagnostics
     }
 
diff --git a/crates/uv/src/commands/pip/check.rs b/crates/uv/src/commands/pip/check.rs
index 86248c1e1..63be05927 100644
--- a/crates/uv/src/commands/pip/check.rs
+++ b/crates/uv/src/commands/pip/check.rs
@@ -5,10 +5,10 @@ use anyhow::Result;
 use owo_colors::OwoColorize;
 use tracing::debug;
 
-use distribution_types::InstalledDist;
+use distribution_types::{Diagnostic, InstalledDist};
 use uv_cache::Cache;
 use uv_fs::Simplified;
-use uv_installer::{Diagnostic, SitePackages};
+use uv_installer::{SitePackages, SitePackagesDiagnostic};
 use uv_interpreter::{PythonEnvironment, SystemPython};
 
 use crate::commands::{elapsed, ExitStatus};
@@ -53,7 +53,8 @@ pub(crate) fn pip_check(
         .dimmed()
     )?;
 
-    let diagnostics: Vec<Diagnostic> = site_packages.diagnostics()?.into_iter().collect();
+    let diagnostics: Vec<SitePackagesDiagnostic> =
+        site_packages.diagnostics()?.into_iter().collect();
 
     if diagnostics.is_empty() {
         writeln!(
diff --git a/crates/uv/src/commands/pip/freeze.rs b/crates/uv/src/commands/pip/freeze.rs
index ff59ed8d9..f9d7db32c 100644
--- a/crates/uv/src/commands/pip/freeze.rs
+++ b/crates/uv/src/commands/pip/freeze.rs
@@ -5,7 +5,7 @@ use itertools::Itertools;
 use owo_colors::OwoColorize;
 use tracing::debug;
 
-use distribution_types::{InstalledDist, Name};
+use distribution_types::{Diagnostic, InstalledDist, Name};
 use uv_cache::Cache;
 use uv_fs::Simplified;
 use uv_installer::SitePackages;
diff --git a/crates/uv/src/commands/pip/list.rs b/crates/uv/src/commands/pip/list.rs
index 1aa17ee9c..504ae90c3 100644
--- a/crates/uv/src/commands/pip/list.rs
+++ b/crates/uv/src/commands/pip/list.rs
@@ -8,7 +8,7 @@ use serde::Serialize;
 use tracing::debug;
 use unicode_width::UnicodeWidthStr;
 
-use distribution_types::{InstalledDist, Name};
+use distribution_types::{Diagnostic, InstalledDist, Name};
 use uv_cache::Cache;
 use uv_fs::Simplified;
 use uv_installer::SitePackages;
diff --git a/crates/uv/src/commands/pip/operations.rs b/crates/uv/src/commands/pip/operations.rs
index b0cf0caba..80a095aca 100644
--- a/crates/uv/src/commands/pip/operations.rs
+++ b/crates/uv/src/commands/pip/operations.rs
@@ -9,7 +9,8 @@ use owo_colors::OwoColorize;
 use tracing::debug;
 
 use distribution_types::{
-    CachedDist, Diagnostic, InstalledDist, Requirement, UnresolvedRequirementSpecification,
+    CachedDist, Diagnostic, InstalledDist, Requirement, ResolutionDiagnostic,
+    UnresolvedRequirementSpecification,
 };
 use distribution_types::{
     DistributionMetadata, IndexLocations, InstalledMetadata, InstalledVersion, LocalDist, Name,
@@ -708,7 +709,7 @@ pub(crate) fn report_modifications(
 
 /// Report any diagnostics on resolved distributions.
 pub(crate) fn diagnose_resolution(
-    diagnostics: &[Diagnostic],
+    diagnostics: &[ResolutionDiagnostic],
     printer: Printer,
 ) -> Result<(), Error> {
     for diagnostic in diagnostics {
diff --git a/crates/uv/src/commands/pip/show.rs b/crates/uv/src/commands/pip/show.rs
index c98da09d6..6df022ddc 100644
--- a/crates/uv/src/commands/pip/show.rs
+++ b/crates/uv/src/commands/pip/show.rs
@@ -6,7 +6,7 @@ use owo_colors::OwoColorize;
 use rustc_hash::FxHashMap;
 use tracing::debug;
 
-use distribution_types::Name;
+use distribution_types::{Diagnostic, Name};
 use uv_cache::Cache;
 use uv_fs::Simplified;
 use uv_installer::SitePackages;