Drop the install hint for a provider the host cannot run (fixes v0.6.0 release run)

src/LinML.Cli/InferencePipeline.cs

@@ -73,7 +73,7 @@ public static SelectionOutcome Select(
             if (!report.AvailableProviders.Contains(candidate)
                 && KnownPlugins.All.Any(p => p.Id == candidate))
             {
-                unavailableReasons[candidate] = ProviderListing.NotListedReason(candidate);
+                unavailableReasons[candidate] = UnavailableReason(candidate);
             }
         }
 
@@ -260,6 +260,13 @@ public static OpenSessionOutcome OpenSession(
             null, decision.SelectedProvider!, fallbackChain);
     }
 
+    /// <summary>
+    /// Why catalog plugin <paramref name="candidate"/> is not available. One this host cannot run
+    /// gets no install hint: <see cref="ProviderArgs.ProviderUnavailableHint"/> says why instead.
+    /// </summary>
+    internal static string UnavailableReason(ProviderId candidate) =>
+        ProviderListing.NotListedReason(candidate, installable: ProviderArgs.NotApplicableNote(candidate) is null);
+
     internal static string FormatSelectionFailure(string? failureReason, ProviderId? preferredProvider)
     {
         var errorMsg = $"Provider selection failed: {failureReason ?? "Unknown reason"}";

src/LinML.Cli/ProviderArgs.cs

@@ -368,10 +368,7 @@ public static IReadOnlyDictionary<string, string> RegisterEpLibraries(
             return null;
         }
 
-        string? gap = Commands.SetupCommand.ArchitectureNote(
-                spec, System.Runtime.InteropServices.RuntimeInformation.ProcessArchitecture.ToString().ToLowerInvariant())
-            ?? Commands.SetupCommand.MigraphXHardwareNote(spec.Id, Commands.SetupCommand.ProbeAmdRocm());
-        if (gap is not null)
+        if (NotApplicableNote(spec.Id) is { } gap)
         {
             return $"{GetShortName(spec.Id)} is not applicable on this host: {gap}.";
         }
@@ -381,6 +378,21 @@ public static IReadOnlyDictionary<string, string> RegisterEpLibraries(
             : null;
     }
 
+    /// <summary>
+    /// Why this host lacks the hardware or architecture to run catalog plugin
+    /// <paramref name="provider"/> (so installing it would not help), or null when it could run here
+    /// or is not a catalog plugin.
+    /// </summary>
+    public static string? NotApplicableNote(ProviderId? provider)
+    {
+        var spec = LinML.Catalog.KnownPlugins.All.FirstOrDefault(p => p.Id == provider);
+        return spec is null
+            ? null
+            : Commands.SetupCommand.ArchitectureNote(
+                    spec, System.Runtime.InteropServices.RuntimeInformation.ProcessArchitecture.ToString().ToLowerInvariant())
+                ?? Commands.SetupCommand.MigraphXHardwareNote(spec.Id, Commands.SetupCommand.ProbeAmdRocm());
+    }
+
     /// <summary>
     /// Registers, in this process, every catalog plugin that resolves on this host, so that
     /// discovery, readiness and catalog status all see the same EP devices. A plugin that

src/LinML.Runtime.Onnx/ProviderListing.cs

@@ -22,9 +22,11 @@ public static bool HasEpDevices(ProviderId provider) =>
 
     /// <summary>
     /// The reason a provider is not listed, worded for the state it is in: built-in, loaded but
-    /// without devices, failed to load (with ORT's message), or not loaded at all.
+    /// without devices, failed to load (with ORT's message), or not loaded at all. Pass
+    /// <paramref name="installable"/> false when the caller knows this host cannot run the
+    /// provider (no ROCm for MIGraphX, say): a plugin that is not loaded then gets no install hint.
     /// </summary>
-    public static string NotListedReason(ProviderId provider)
+    public static string NotListedReason(ProviderId provider, bool installable = true)
     {
         var plugin = KnownPlugins.All.FirstOrDefault(p => p.Id == provider);
         if (plugin is null)
@@ -51,7 +53,9 @@ public static string NotListedReason(ProviderId provider)
             return $"Provider '{provider}' is installed but failed to register: {failure}";
         }
 
-        return $"Provider '{provider}' is not loaded into this process. If the plugin is not installed, run 'linml catalog install {ShortName(provider)}' to vendor it.";
+        return installable
+            ? $"Provider '{provider}' is not loaded into this process. If the plugin is not installed, run 'linml catalog install {ShortName(provider)}' to vendor it."
+            : $"Provider '{provider}' is not loaded into this process.";
     }
 
     // Matches the CLI's short names for these providers (ProviderArgs.GetShortName).

tests/LinML.Cli.Tests/ProviderArgsTests.cs

@@ -519,4 +519,21 @@ public void ResolveEpLibraries_Wsl_ExplicitAndNonStockMappings_StayAuthoritative
             [$"NvTensorRTRTXExecutionProvider={layout.Stock}"], ProviderId.TensorrtRtx, layout.Root);
         Assert.Equal(layout.Stock, explicitArg["NvTensorRTRTXExecutionProvider"]);
     }
+
+    // The selection failure for a provider this host cannot run must not tell the user to install
+    // it, whatever this process has registered: `run --require-provider migraphx` on a host without
+    // ROCm printed the not-applicable hint and an install hint from the listing reason.
+    [Fact]
+    public void UnavailableReason_ProviderTheHostCannotRun_HasNoInstallHint()
+    {
+        // MIGraphX without ROCm reaches the generic not-loaded reason; a plugin for another
+        // architecture (QNN on x64) is already worded as such and never had the hint.
+        if (Commands.SetupCommand.ProbeAmdRocm())
+        {
+            return;
+        }
+
+        Assert.NotNull(ProviderArgs.NotApplicableNote(ProviderId.MigraphX));
+        Assert.DoesNotContain("catalog install", InferencePipeline.UnavailableReason(ProviderId.MigraphX), StringComparison.Ordinal);
+    }
 }

tests/LinML.Runtime.Onnx.Tests/ProviderListingTests.cs

@@ -38,6 +38,22 @@ public void NotListedReason_UnloadedPlugin_SuggestsInstallWithShortId()
         Assert.Contains("linml catalog install openvino", reason, StringComparison.Ordinal);
     }
 
+    [Fact]
+    public void NotListedReason_UnloadedPluginTheHostCannotRun_HasNoInstallHint()
+    {
+        const string openVinoLibrary = "libonnxruntime_providers_openvino_plugin.so";
+        if (!OpenVinoRunsOnThisHost || PluginLibraryRegistry.RegisteredLibraryFileNames.Contains(openVinoLibrary)
+            || PluginLibraryRegistry.RegistrationFailure(openVinoLibrary) is not null)
+        {
+            return;
+        }
+
+        string reason = ProviderListing.NotListedReason(ProviderId.OpenVino, installable: false);
+
+        Assert.Contains("is not loaded into this process", reason, StringComparison.Ordinal);
+        Assert.DoesNotContain("catalog install", reason, StringComparison.Ordinal);
+    }
+
     [Fact]
     public void NotListedReason_PluginForAnotherArchitecture_SaysItWillNotRunHere()
     {