feat: Implement approvals workflow and notifications integration

- Added approvals orchestration with persistence and workflow scaffolding.
- Integrated notifications insights and staged resume hooks.
- Introduced approval coordinator and policy notification bridge with unit tests.
- Added approval decision API with resume requeue and persisted plan snapshots.
- Documented the Excitor consensus API beta and provided JSON sample payload.
- Created analyzers to flag usage of deprecated merge service APIs.
- Implemented logging for artifact uploads and approval decision service.
- Added tests for PackRunApprovalDecisionService and related components.

src/Excititor/StellaOps.Excititor.Worker/Signature/WorkerSignatureVerifier.cs

@@ -84,10 +84,13 @@ internal sealed class WorkerSignatureVerifier : IVexSignatureVerifier
             throw new ExcititorAocGuardException(AocGuardResult.FromViolations(new[] { violation }));
         }
 
-        VexSignatureMetadata? signatureMetadata = null;
-        if (document.Format == VexDocumentFormat.OciAttestation && _attestationVerifier is not null)
+        VexSignatureMetadata? signatureMetadata = null;
+        VexAttestationDiagnostics? attestationDiagnostics = null;
+        if (document.Format == VexDocumentFormat.OciAttestation && _attestationVerifier is not null)
         {
-            signatureMetadata = await VerifyAttestationAsync(document, metadata, cancellationToken).ConfigureAwait(false);
+            var attestationResult = await VerifyAttestationAsync(document, metadata, cancellationToken).ConfigureAwait(false);
+            signatureMetadata = attestationResult.Metadata;
+            attestationDiagnostics = attestationResult.Diagnostics;
         }
 
         signatureMetadata ??= ExtractSignatureMetadata(metadata);
@@ -96,31 +99,40 @@ internal sealed class WorkerSignatureVerifier : IVexSignatureVerifier
             signatureMetadata = await AttachIssuerTrustAsync(signatureMetadata, metadata, cancellationToken).ConfigureAwait(false);
         }
         var resultLabel = signatureMetadata is null ? "skipped" : "ok";
-        RecordVerification(document.ProviderId, metadata, resultLabel);
-
-        if (resultLabel == "skipped")
-        {
+        if (attestationDiagnostics is not null)
+        {
+            resultLabel = attestationDiagnostics.Result ?? resultLabel;
+        }
+
+        if (attestationDiagnostics is null)
+        {
+            RecordVerification(document.ProviderId, metadata, resultLabel);
+        }
+
+        if (resultLabel == "skipped")
+        {
             _logger.LogDebug(
                 "Signature verification skipped for provider {ProviderId} (no signature metadata).",
                 document.ProviderId);
         }
         else
         {
-            _logger.LogInformation(
-                "Signature metadata recorded for provider {ProviderId} (type={SignatureType}, subject={Subject}, issuer={Issuer}).",
-                document.ProviderId,
-                signatureMetadata!.Type,
-                signatureMetadata.Subject ?? "<unknown>",
-                signatureMetadata.Issuer ?? "<unknown>");
-        }
-
-        return signatureMetadata;
-    }
-
-    private async ValueTask<VexSignatureMetadata?> VerifyAttestationAsync(
-        VexRawDocument document,
-        ImmutableDictionary<string, string> metadata,
-        CancellationToken cancellationToken)
+            _logger.LogInformation(
+                "Signature metadata recorded for provider {ProviderId} (type={SignatureType}, subject={Subject}, issuer={Issuer}, result={Result}).",
+                document.ProviderId,
+                signatureMetadata!.Type,
+                signatureMetadata.Subject ?? "<unknown>",
+                signatureMetadata.Issuer ?? "<unknown>",
+                resultLabel);
+        }
+
+        return signatureMetadata;
+    }
+
+    private async ValueTask<(VexSignatureMetadata Metadata, VexAttestationDiagnostics Diagnostics)> VerifyAttestationAsync(
+        VexRawDocument document,
+        ImmutableDictionary<string, string> metadata,
+        CancellationToken cancellationToken)
     {
         try
         {
@@ -146,37 +158,48 @@ internal sealed class WorkerSignatureVerifier : IVexSignatureVerifier
                 attestationMetadata,
                 envelopeJson);
 
-            var verification = await _attestationVerifier!
-                .VerifyAsync(verificationRequest, cancellationToken)
-                .ConfigureAwait(false);
-            if (!verification.IsValid)
-            {
-                var diagnostics = string.Join(", ", verification.Diagnostics.Select(kvp => $"{kvp.Key}={kvp.Value}"));
-                _logger.LogError(
-                    "Attestation verification failed for provider {ProviderId} (uri={SourceUri}) diagnostics={Diagnostics}",
-                    document.ProviderId,
-                    document.SourceUri,
-                    diagnostics);
-
-                var violation = AocViolation.Create(
-                    AocViolationCode.SignatureInvalid,
-                    "/upstream/signature",
-                    "Attestation verification failed.");
-
-                RecordVerification(document.ProviderId, metadata, "fail");
-                throw new ExcititorAocGuardException(AocGuardResult.FromViolations(new[] { violation }));
-            }
-
-            _logger.LogInformation(
-                "Attestation verification succeeded for provider {ProviderId} (predicate={PredicateType}, subject={Subject}).",
-                document.ProviderId,
-                attestationMetadata.PredicateType,
-                statement.Subject[0].Name ?? "<unknown>");
-
-            return BuildSignatureMetadata(statement, metadata, attestationMetadata, verification.Diagnostics);
-        }
-        catch (ExcititorAocGuardException)
-        {
+            var verification = await _attestationVerifier!
+                .VerifyAsync(verificationRequest, cancellationToken)
+                .ConfigureAwait(false);
+            var diagnosticsSnapshot = verification.Diagnostics;
+
+            if (!verification.IsValid)
+            {
+                var failureReason = diagnosticsSnapshot.FailureReason ?? "verification_failed";
+                var resultTag = diagnosticsSnapshot.Result ?? "invalid";
+
+                RecordVerification(document.ProviderId, metadata, resultTag);
+                _logger.LogError(
+                    "Attestation verification failed for provider {ProviderId} (uri={SourceUri}) result={Result} failure={FailureReason} diagnostics={@Diagnostics}",
+                    document.ProviderId,
+                    document.SourceUri,
+                    resultTag,
+                    failureReason,
+                    diagnosticsSnapshot);
+
+                var violation = AocViolation.Create(
+                    AocViolationCode.SignatureInvalid,
+                    "/upstream/signature",
+                    "Attestation verification failed.");
+
+                throw new ExcititorAocGuardException(AocGuardResult.FromViolations(new[] { violation }));
+            }
+
+            var successResult = diagnosticsSnapshot.Result ?? "valid";
+            RecordVerification(document.ProviderId, metadata, successResult);
+
+            _logger.LogInformation(
+                "Attestation verification succeeded for provider {ProviderId} (predicate={PredicateType}, subject={Subject}, result={Result}).",
+                document.ProviderId,
+                attestationMetadata.PredicateType,
+                statement.Subject[0].Name ?? "<unknown>",
+                successResult);
+
+            var signatureMetadata = BuildSignatureMetadata(statement, metadata, attestationMetadata, diagnosticsSnapshot);
+            return (signatureMetadata, diagnosticsSnapshot);
+        }
+        catch (ExcititorAocGuardException)
+        {
             throw;
         }
         catch (Exception ex)
@@ -192,10 +215,10 @@ internal sealed class WorkerSignatureVerifier : IVexSignatureVerifier
                 "/upstream/signature",
                 $"Attestation verification encountered an error: {ex.Message}");
 
-            RecordVerification(document.ProviderId, metadata, "fail");
-            throw new ExcititorAocGuardException(AocGuardResult.FromViolations(new[] { violation }));
-        }
-    }
+            RecordVerification(document.ProviderId, metadata, "error");
+            throw new ExcititorAocGuardException(AocGuardResult.FromViolations(new[] { violation }));
+        }
+    }
 
     private VexAttestationRequest BuildAttestationRequest(VexInTotoStatement statement, VexAttestationPredicate predicate)
     {
@@ -252,11 +275,11 @@ internal sealed class WorkerSignatureVerifier : IVexSignatureVerifier
             signedAt);
     }
 
-    private VexSignatureMetadata BuildSignatureMetadata(
-        VexInTotoStatement statement,
-        ImmutableDictionary<string, string> metadata,
-        VexAttestationMetadata attestationMetadata,
-        ImmutableDictionary<string, string> diagnostics)
+    private VexSignatureMetadata BuildSignatureMetadata(
+        VexInTotoStatement statement,
+        ImmutableDictionary<string, string> metadata,
+        VexAttestationMetadata attestationMetadata,
+        VexAttestationDiagnostics diagnostics)
     {
         metadata.TryGetValue("vex.signature.type", out var type);
         metadata.TryGetValue("vex.provenance.cosign.subject", out var subject);

src/Excititor/__Libraries/StellaOps.Excititor.Attestation/EXCITITOR-ATTEST-01-003-plan.md

@@ -13,16 +13,18 @@
 3. Emit observability signals (logs, metrics, optional tracing) that can run offline and degrade gracefully when transparency services are unreachable.
 4. Add regression tests (unit + integration) covering positive path, negative path, and offline fallback scenarios.
 
-## 2. Deliverables
-
-- `IVexAttestationVerifier` abstraction + `VexAttestationVerifier` implementation inside `StellaOps.Excititor.Attestation`, encapsulating DSSE validation, predicate checks, artifact digest confirmation, Rekor inclusion verification, and deterministic diagnostics.
-- DI wiring (extension method) for registering verifier + instrumentation dependencies alongside the existing signer/rekor client.
-- Shared `VexAttestationDiagnostics` record describing normalized diagnostic keys consumed by Worker/WebService logging.
-- Metrics utility (`AttestationMetrics`) exposing counters/histograms via `System.Diagnostics.Metrics`, exported under `StellaOps.Excititor.Attestation` meter.
-- Activity source (`AttestationActivitySource`) for optional tracing spans around sign/verify operations.
-- Documentation updates (`EXCITITOR-ATTEST-01-003-plan.md`, `TASKS.md` notes) describing instrumentation + test expectations.
-- Test coverage in `StellaOps.Excititor.Attestation.Tests` (unit) and scaffolding notes for WebService/Worker integration tests.
-
+## 2. Deliverables
+
+- `IVexAttestationVerifier` abstraction + `VexAttestationVerifier` implementation inside `StellaOps.Excititor.Attestation`, encapsulating DSSE validation, predicate checks, artifact digest confirmation, Rekor inclusion verification, and deterministic diagnostics.
+- DI wiring (extension method) for registering verifier + instrumentation dependencies alongside the existing signer/rekor client.
+- Shared `VexAttestationDiagnostics` record describing normalized diagnostic keys consumed by Worker/WebService logging.
+- Metrics utility (`AttestationMetrics`) exposing counters/histograms via `System.Diagnostics.Metrics`, exported under `StellaOps.Excititor.Attestation` meter.
+- Activity source (`AttestationActivitySource`) for optional tracing spans around sign/verify operations.
+- 2025-11-05: Implemented `VexAttestationDiagnostics`, activity tagging via `VexAttestationActivitySource`, and updated verifier/tests to emit structured failure reasons.
+- 2025-11-05 (pm): Worker attestation verifier now records structured diagnostics/metrics and logs result/failure reasons using `VexAttestationDiagnostics`; attestation success/failure labels propagate to verification counters.
+- Documentation updates (`EXCITITOR-ATTEST-01-003-plan.md`, `TASKS.md` notes) describing instrumentation + test expectations.
+- Test coverage in `StellaOps.Excititor.Attestation.Tests` (unit) and scaffolding notes for WebService/Worker integration tests.
+
 ## 3. Verification Flow
 
 ### 3.1 Inputs

src/Excititor/__Libraries/StellaOps.Excititor.Attestation/TASKS.md

@@ -1,6 +1,7 @@
-If you are working on this file you need to read docs/modules/excititor/ARCHITECTURE.md and ./AGENTS.md).
-# TASKS
-| Task | Owner(s) | Depends on | Notes |
-|---|---|---|---|
-|EXCITITOR-ATTEST-01-003 – Verification suite & observability|Team Excititor Attestation|EXCITITOR-ATTEST-01-002|DOING (2025-10-22) – Continuing implementation: build `IVexAttestationVerifier`, wire metrics/logging, and add regression tests. Draft plan in `EXCITITOR-ATTEST-01-003-plan.md` (2025-10-19) guides scope; updating with worknotes as progress lands.<br>2025-10-31: Verifier now tolerates duplicate source providers from AOC raw projections, downgrades offline Rekor verification to a degraded result, and enforces trusted signer registry checks with detailed diagnostics/tests.|
-
+If you are working on this file you need to read docs/modules/excititor/ARCHITECTURE.md and ./AGENTS.md).
+# TASKS
+| Task | Owner(s) | Depends on | Notes |
+|---|---|---|---|
+|EXCITITOR-ATTEST-01-003 – Verification suite & observability|Team Excititor Attestation|EXCITITOR-ATTEST-01-002|DOING (2025-10-22) – Continuing implementation: build `IVexAttestationVerifier`, wire metrics/logging, and add regression tests. Draft plan in `EXCITITOR-ATTEST-01-003-plan.md` (2025-10-19) guides scope; updating with worknotes as progress lands.<br>2025-10-31: Verifier now tolerates duplicate source providers from AOC raw projections, downgrades offline Rekor verification to a degraded result, and enforces trusted signer registry checks with detailed diagnostics/tests.<br>2025-11-05 14:35Z: Picking up diagnostics record/ActivitySource work and aligning metrics dimensions before wiring verifier into WebService/Worker paths.|
+> 2025-11-05 19:10Z: Worker signature verifier now emits structured diagnostics/metrics via `VexAttestationDiagnostics`; attestation verification results flow into metric labels and logs.
+> Remark (2025-10-22): Added verifier implementation + metrics/tests; next steps include wiring into WebService/Worker flows and expanding negative-path coverage.

src/Excititor/__Libraries/StellaOps.Excititor.Attestation/Verification/VexAttestationActivitySource.cs

@@ -0,0 +1,10 @@
+using System.Diagnostics;
+
+namespace StellaOps.Excititor.Attestation.Verification;
+
+public static class VexAttestationActivitySource
+{
+    public const string Name = "StellaOps.Excititor.Attestation";
+
+    public static readonly ActivitySource Value = new(Name);
+}

src/Excititor/__Libraries/StellaOps.Excititor.Attestation/Verification/VexAttestationVerifier.cs

@@ -1,8 +1,8 @@
 using System;
-using System.Collections.Generic;
-using System.Collections.Immutable;
-using System.Diagnostics;
-using System.Linq;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Diagnostics;
+using System.Linq;
 using System.Text;
 using System.Text.Json;
 using System.Text.Json.Serialization;
@@ -59,104 +59,120 @@ internal sealed class VexAttestationVerifier : IVexAttestationVerifier
     public async ValueTask<VexAttestationVerification> VerifyAsync(
         VexAttestationVerificationRequest request,
         CancellationToken cancellationToken)
-    {
-        ArgumentNullException.ThrowIfNull(request);
-
-        var stopwatch = Stopwatch.StartNew();
-        var diagnostics = ImmutableDictionary.CreateBuilder<string, string>(StringComparer.Ordinal);
+    {
+        ArgumentNullException.ThrowIfNull(request);
+
+        var stopwatch = Stopwatch.StartNew();
+        var diagnostics = ImmutableDictionary.CreateBuilder<string, string>(StringComparer.Ordinal);
         var resultLabel = "valid";
         var rekorState = "skipped";
         var component = request.IsReverify ? "worker" : "webservice";
+        void SetFailure(string reason) => diagnostics["failure_reason"] = reason;
+        using var activity = VexAttestationActivitySource.Value.StartActivity("Verify", ActivityKind.Internal);
+        activity?.SetTag("attestation.component", component);
+        activity?.SetTag("attestation.export_id", request.Attestation.ExportId);
 
         try
         {
-            if (string.IsNullOrWhiteSpace(request.Envelope))
-            {
-                diagnostics["envelope.state"] = "missing";
-                _logger.LogWarning("Attestation envelope is missing for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!TryDeserializeEnvelope(request.Envelope, out var envelope, diagnostics))
-            {
-                _logger.LogWarning("Failed to deserialize attestation envelope for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!string.Equals(envelope.PayloadType, VexDsseBuilder.PayloadType, StringComparison.OrdinalIgnoreCase))
-            {
-                diagnostics["payload.type"] = envelope.PayloadType ?? string.Empty;
-                _logger.LogWarning(
-                    "Unexpected DSSE payload type {PayloadType} for export {ExportId}",
-                    envelope.PayloadType,
-                    request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (envelope.Signatures is null || envelope.Signatures.Count == 0)
-            {
-                diagnostics["signature.state"] = "missing";
-                _logger.LogWarning("Attestation envelope for export {ExportId} does not contain signatures.", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            var payloadBase64 = envelope.Payload ?? string.Empty;
-            if (!TryDecodePayload(payloadBase64, out var payloadBytes, diagnostics))
-            {
-                _logger.LogWarning("Failed to decode attestation payload for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!TryDeserializeStatement(payloadBytes, out var statement, diagnostics))
-            {
-                _logger.LogWarning("Failed to deserialize DSSE statement for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!ValidatePredicateType(statement, request, diagnostics))
-            {
-                _logger.LogWarning("Predicate type mismatch for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!ValidateSubject(statement, request, diagnostics))
-            {
-                _logger.LogWarning("Subject mismatch for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!ValidatePredicate(statement, request, diagnostics))
-            {
-                _logger.LogWarning("Predicate payload mismatch for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!ValidateMetadataDigest(envelope, request.Metadata, diagnostics))
-            {
-                _logger.LogWarning("Attestation digest mismatch for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
-            if (!ValidateSignedAt(request.Metadata, request.Attestation.CreatedAt, diagnostics))
-            {
-                _logger.LogWarning("SignedAt validation failed for export {ExportId}", request.Attestation.ExportId);
-                resultLabel = "invalid";
-                return BuildResult(false);
-            }
-
+            if (string.IsNullOrWhiteSpace(request.Envelope))
+            {
+                diagnostics["envelope.state"] = "missing";
+                SetFailure("missing_envelope");
+                _logger.LogWarning("Attestation envelope is missing for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!TryDeserializeEnvelope(request.Envelope, out var envelope, diagnostics))
+            {
+                SetFailure("invalid_envelope");
+                _logger.LogWarning("Failed to deserialize attestation envelope for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!string.Equals(envelope.PayloadType, VexDsseBuilder.PayloadType, StringComparison.OrdinalIgnoreCase))
+            {
+                diagnostics["payload.type"] = envelope.PayloadType ?? string.Empty;
+                SetFailure("unexpected_payload_type");
+                _logger.LogWarning(
+                    "Unexpected DSSE payload type {PayloadType} for export {ExportId}",
+                    envelope.PayloadType,
+                    request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (envelope.Signatures is null || envelope.Signatures.Count == 0)
+            {
+                diagnostics["signature.state"] = "missing";
+                SetFailure("missing_signature");
+                _logger.LogWarning("Attestation envelope for export {ExportId} does not contain signatures.", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            var payloadBase64 = envelope.Payload ?? string.Empty;
+            if (!TryDecodePayload(payloadBase64, out var payloadBytes, diagnostics))
+            {
+                SetFailure("payload_decode_failed");
+                _logger.LogWarning("Failed to decode attestation payload for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!TryDeserializeStatement(payloadBytes, out var statement, diagnostics))
+            {
+                SetFailure("invalid_statement");
+                _logger.LogWarning("Failed to deserialize DSSE statement for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!ValidatePredicateType(statement, request, diagnostics))
+            {
+                SetFailure("predicate_type_mismatch");
+                _logger.LogWarning("Predicate type mismatch for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!ValidateSubject(statement, request, diagnostics))
+            {
+                SetFailure("subject_mismatch");
+                _logger.LogWarning("Subject mismatch for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!ValidatePredicate(statement, request, diagnostics))
+            {
+                SetFailure("predicate_mismatch");
+                _logger.LogWarning("Predicate payload mismatch for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!ValidateMetadataDigest(envelope, request.Metadata, diagnostics))
+            {
+                SetFailure("envelope_digest_mismatch");
+                _logger.LogWarning("Attestation digest mismatch for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
+            if (!ValidateSignedAt(request.Metadata, request.Attestation.CreatedAt, diagnostics))
+            {
+                SetFailure("signedat_out_of_range");
+                _logger.LogWarning("SignedAt validation failed for export {ExportId}", request.Attestation.ExportId);
+                resultLabel = "invalid";
+                return BuildResult(false);
+            }
+
             rekorState = await VerifyTransparencyAsync(request.Metadata, diagnostics, cancellationToken).ConfigureAwait(false);
             if (rekorState is "missing" or "unverified" or "client_unavailable")
             {
+                SetFailure(rekorState);
                 resultLabel = "invalid";
                 return BuildResult(false);
             }
@@ -164,6 +180,9 @@ internal sealed class VexAttestationVerifier : IVexAttestationVerifier
             var signaturesVerified = await VerifySignaturesAsync(payloadBytes, envelope.Signatures, diagnostics, cancellationToken).ConfigureAwait(false);
             if (!signaturesVerified)
             {
+                diagnostics["failure_reason"] = diagnostics.TryGetValue("signature.reason", out var reason)
+                    ? reason
+                    : "signature_verification_failed";
                 if (_options.RequireSignatureVerification)
                 {
                     resultLabel = "invalid";
@@ -183,13 +202,16 @@ internal sealed class VexAttestationVerifier : IVexAttestationVerifier
         catch (Exception ex)
         {
             diagnostics["error"] = ex.GetType().Name;
-            diagnostics["error.message"] = ex.Message;            resultLabel = "error";
-            _logger.LogError(ex, "Unexpected exception verifying attestation for export {ExportId}", request.Attestation.ExportId);
-            return BuildResult(false);
-        }
-        finally
-        {
-            stopwatch.Stop();
+            diagnostics["error.message"] = ex.Message;            resultLabel = "error";
+            _logger.LogError(ex, "Unexpected exception verifying attestation for export {ExportId}", request.Attestation.ExportId);
+            diagnostics["failure_reason"] = diagnostics.TryGetValue("error", out var errorCode)
+                ? errorCode
+                : ex.GetType().Name;
+            return BuildResult(false);
+        }
+        finally
+        {
+            stopwatch.Stop();
             var tags = new KeyValuePair<string, object?>[]
             {
                 new("result", resultLabel),
@@ -200,12 +222,32 @@ internal sealed class VexAttestationVerifier : IVexAttestationVerifier
             _metrics.VerifyDuration.Record(stopwatch.Elapsed.TotalSeconds, tags);
         }
 
-        VexAttestationVerification BuildResult(bool isValid)
-        {
-            diagnostics["result"] = resultLabel;
-            diagnostics["component"] = component;
+        VexAttestationVerification BuildResult(bool isValid)
+        {
+            diagnostics["result"] = resultLabel;
+            diagnostics["component"] = component;
             diagnostics["rekor.state"] = rekorState;
-            return new VexAttestationVerification(isValid, diagnostics.ToImmutable());
+            var snapshot = VexAttestationDiagnostics.FromBuilder(diagnostics);
+
+            if (activity is { } currentActivity)
+            {
+                currentActivity.SetTag("attestation.result", resultLabel);
+                currentActivity.SetTag("attestation.rekor", rekorState);
+                if (!isValid)
+                {
+                    var failure = snapshot.FailureReason ?? "verification_failed";
+                    currentActivity.SetStatus(ActivityStatusCode.Error, failure);
+                    currentActivity.SetTag("attestation.failure_reason", failure);
+                }
+                else
+                {
+                    currentActivity.SetStatus(resultLabel is "degraded"
+                        ? ActivityStatusCode.Ok
+                        : ActivityStatusCode.Ok);
+                }
+            }
+
+            return new VexAttestationVerification(isValid, snapshot);
         }
     }
 

src/Excititor/__Libraries/StellaOps.Excititor.Core/StellaOps.Excititor.Core.csproj

@@ -14,4 +14,4 @@
     <ProjectReference Include="../../../Aoc/__Libraries/StellaOps.Aoc/StellaOps.Aoc.csproj" />
     <ProjectReference Include="../../../Concelier/__Libraries/StellaOps.Concelier.RawModels/StellaOps.Concelier.RawModels.csproj" />
   </ItemGroup>
-</Project>
+</Project>

src/Excititor/__Libraries/StellaOps.Excititor.Core/VexAttestationAbstractions.cs

@@ -1,7 +1,8 @@
 using System;
 using System.Collections.Immutable;
 using System.Threading;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
+using StellaOps.Excititor.Attestation.Verification;
 
 namespace StellaOps.Excititor.Core;
 
@@ -33,4 +34,4 @@ public sealed record VexAttestationVerificationRequest(
 
 public sealed record VexAttestationVerification(
     bool IsValid,
-    ImmutableDictionary<string, string> Diagnostics);
+    VexAttestationDiagnostics Diagnostics);

src/Excititor/__Libraries/StellaOps.Excititor.Core/VexAttestationDiagnostics.cs

@@ -0,0 +1,57 @@
+using System.Collections;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+
+namespace StellaOps.Excititor.Attestation.Verification;
+
+public sealed class VexAttestationDiagnostics : IReadOnlyDictionary<string, string>
+{
+    private readonly ImmutableDictionary<string, string> _values;
+
+    private VexAttestationDiagnostics(ImmutableDictionary<string, string> values)
+    {
+        _values = values ?? ImmutableDictionary<string, string>.Empty;
+    }
+
+    public static VexAttestationDiagnostics FromBuilder(ImmutableDictionary<string, string>.Builder builder)
+    {
+        ArgumentNullException.ThrowIfNull(builder);
+        return new(builder.ToImmutable());
+    }
+
+    public static VexAttestationDiagnostics Empty { get; } = new(ImmutableDictionary<string, string>.Empty);
+
+    public string? Result => TryGetValue("result", out var value) ? value : null;
+
+    public string? Component => TryGetValue("component", out var value) ? value : null;
+
+    public string? RekorState => TryGetValue("rekor.state", out var value) ? value : null;
+
+    public string? FailureReason => TryGetValue("failure_reason", out var value) ? value : null;
+
+    public string this[string key] => _values[key];
+
+    public IEnumerable<string> Keys => _values.Keys;
+
+    public IEnumerable<string> Values => _values.Values;
+
+    public int Count => _values.Count;
+
+    public bool ContainsKey(string key) => _values.ContainsKey(key);
+
+    public bool TryGetValue(string key, out string value)
+    {
+        if (_values.TryGetValue(key, out var stored))
+        {
+            value = stored;
+            return true;
+        }
+
+        value = string.Empty;
+        return false;
+    }
+
+    public IEnumerator<KeyValuePair<string, string>> GetEnumerator() => _values.GetEnumerator();
+
+    IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+}

src/Excititor/__Tests/StellaOps.Excititor.Attestation.Tests/VexAttestationClientTests.cs

@@ -85,6 +85,6 @@ public sealed class VexAttestationClientTests
     private sealed class FakeVerifier : IVexAttestationVerifier
     {
         public ValueTask<VexAttestationVerification> VerifyAsync(VexAttestationVerificationRequest request, CancellationToken cancellationToken)
-            => ValueTask.FromResult(new VexAttestationVerification(true, ImmutableDictionary<string, string>.Empty));
+            => ValueTask.FromResult(new VexAttestationVerification(true, VexAttestationDiagnostics.Empty));
     }
 }

src/Excititor/__Tests/StellaOps.Excititor.Attestation.Tests/VexAttestationVerifierTests.cs

@@ -16,42 +16,44 @@ public sealed class VexAttestationVerifierTests : IDisposable
 {
     private readonly VexAttestationMetrics _metrics = new();
 
-    [Fact]
-    public async Task VerifyAsync_ReturnsValid_WhenEnvelopeMatches()
-    {
-        var (request, metadata, envelope) = await CreateSignedAttestationAsync();
-        var verifier = CreateVerifier(options => options.RequireTransparencyLog = false);
+    [Fact]
+    public async Task VerifyAsync_ReturnsValid_WhenEnvelopeMatches()
+    {
+        var (request, metadata, envelope) = await CreateSignedAttestationAsync();
+        var verifier = CreateVerifier(options => options.RequireTransparencyLog = false);
+
+        var verification = await verifier.VerifyAsync(
+            new VexAttestationVerificationRequest(request, metadata, envelope),
+            CancellationToken.None);
+
+        Assert.True(verification.IsValid);
+        Assert.Equal("valid", verification.Diagnostics.Result);
+        Assert.Null(verification.Diagnostics.FailureReason);
+    }
 
-        var verification = await verifier.VerifyAsync(
-            new VexAttestationVerificationRequest(request, metadata, envelope),
-            CancellationToken.None);
+    [Fact]
+    public async Task VerifyAsync_ReturnsInvalid_WhenDigestMismatch()
+    {
+        var (request, metadata, envelope) = await CreateSignedAttestationAsync();
+        var verifier = CreateVerifier(options => options.RequireTransparencyLog = false);
+
+        var tamperedMetadata = new VexAttestationMetadata(
+            metadata.PredicateType,
+            metadata.Rekor,
+            "sha256:deadbeef",
+            metadata.SignedAt);
+
+        var verification = await verifier.VerifyAsync(
+            new VexAttestationVerificationRequest(request, tamperedMetadata, envelope),
+            CancellationToken.None);
+
+        Assert.False(verification.IsValid);
+        Assert.Equal("invalid", verification.Diagnostics.Result);
+        Assert.Equal("sha256:deadbeef", verification.Diagnostics["metadata.envelopeDigest"]);
+        Assert.Equal("envelope_digest_mismatch", verification.Diagnostics.FailureReason);
+    }
 
-        Assert.True(verification.IsValid);
-        Assert.Equal("valid", verification.Diagnostics["result"]);
-    }
-
-    [Fact]
-    public async Task VerifyAsync_ReturnsInvalid_WhenDigestMismatch()
-    {
-        var (request, metadata, envelope) = await CreateSignedAttestationAsync();
-        var verifier = CreateVerifier(options => options.RequireTransparencyLog = false);
-
-        var tamperedMetadata = new VexAttestationMetadata(
-            metadata.PredicateType,
-            metadata.Rekor,
-            "sha256:deadbeef",
-            metadata.SignedAt);
-
-        var verification = await verifier.VerifyAsync(
-            new VexAttestationVerificationRequest(request, tamperedMetadata, envelope),
-            CancellationToken.None);
-
-        Assert.False(verification.IsValid);
-        Assert.Equal("invalid", verification.Diagnostics["result"]);
-        Assert.Equal("sha256:deadbeef", verification.Diagnostics["metadata.envelopeDigest"]);
-    }
-
-    [Fact]
+    [Fact]
     public async Task VerifyAsync_AllowsOfflineTransparency_WhenConfigured()
     {
         var (request, metadata, envelope) = await CreateSignedAttestationAsync(includeRekor: true);
@@ -67,47 +69,50 @@ public sealed class VexAttestationVerifierTests : IDisposable
             CancellationToken.None);
 
         Assert.True(verification.IsValid);
-        Assert.Equal("offline", verification.Diagnostics["rekor.state"]);
-        Assert.Equal("degraded", verification.Diagnostics["result"]);
+        Assert.Equal("offline", verification.Diagnostics.RekorState);
+        Assert.Equal("degraded", verification.Diagnostics.Result);
+        Assert.Null(verification.Diagnostics.FailureReason);
     }
 
     [Fact]
     public async Task VerifyAsync_ReturnsInvalid_WhenTransparencyRequiredAndMissing()
-    {
-        var (request, metadata, envelope) = await CreateSignedAttestationAsync(includeRekor: false);
-        var verifier = CreateVerifier(options =>
-        {
-            options.RequireTransparencyLog = true;
-            options.AllowOfflineTransparency = false;
-        });
-
-        var verification = await verifier.VerifyAsync(
-            new VexAttestationVerificationRequest(request, metadata, envelope),
-            CancellationToken.None);
-
-        Assert.False(verification.IsValid);
-        Assert.Equal("missing", verification.Diagnostics["rekor.state"]);
-        Assert.Equal("invalid", verification.Diagnostics["result"]);
-    }
-
-    [Fact]
-    public async Task VerifyAsync_ReturnsInvalid_WhenTransparencyUnavailableAndOfflineDisallowed()
-    {
-        var (request, metadata, envelope) = await CreateSignedAttestationAsync(includeRekor: true);
-        var transparency = new ThrowingTransparencyLogClient();
-        var verifier = CreateVerifier(options =>
-        {
-            options.RequireTransparencyLog = true;
-            options.AllowOfflineTransparency = false;
-        }, transparency);
-
-        var verification = await verifier.VerifyAsync(
-            new VexAttestationVerificationRequest(request, metadata, envelope),
-            CancellationToken.None);
-
-        Assert.False(verification.IsValid);
-        Assert.Equal("unreachable", verification.Diagnostics["rekor.state"]);
-        Assert.Equal("invalid", verification.Diagnostics["result"]);
+    {
+        var (request, metadata, envelope) = await CreateSignedAttestationAsync(includeRekor: false);
+        var verifier = CreateVerifier(options =>
+        {
+            options.RequireTransparencyLog = true;
+            options.AllowOfflineTransparency = false;
+        });
+
+        var verification = await verifier.VerifyAsync(
+            new VexAttestationVerificationRequest(request, metadata, envelope),
+            CancellationToken.None);
+
+        Assert.False(verification.IsValid);
+        Assert.Equal("missing", verification.Diagnostics.RekorState);
+        Assert.Equal("invalid", verification.Diagnostics.Result);
+        Assert.Equal("missing", verification.Diagnostics.FailureReason);
+    }
+
+    [Fact]
+    public async Task VerifyAsync_ReturnsInvalid_WhenTransparencyUnavailableAndOfflineDisallowed()
+    {
+        var (request, metadata, envelope) = await CreateSignedAttestationAsync(includeRekor: true);
+        var transparency = new ThrowingTransparencyLogClient();
+        var verifier = CreateVerifier(options =>
+        {
+            options.RequireTransparencyLog = true;
+            options.AllowOfflineTransparency = false;
+        }, transparency);
+
+        var verification = await verifier.VerifyAsync(
+            new VexAttestationVerificationRequest(request, metadata, envelope),
+            CancellationToken.None);
+
+        Assert.False(verification.IsValid);
+        Assert.Equal("unreachable", verification.Diagnostics.RekorState);
+        Assert.Equal("invalid", verification.Diagnostics.Result);
+        Assert.Equal("unreachable", verification.Diagnostics.FailureReason);
     }
 
     [Fact]
@@ -125,7 +130,7 @@ public sealed class VexAttestationVerifierTests : IDisposable
             CancellationToken.None);
 
         Assert.True(verification.IsValid);
-        Assert.Equal("valid", verification.Diagnostics["result"]);
+        Assert.Equal("valid", verification.Diagnostics.Result);
     }
 
     [Fact]
@@ -152,6 +157,8 @@ public sealed class VexAttestationVerifierTests : IDisposable
 
         Assert.True(verification.IsValid);
         Assert.Equal("verified", verification.Diagnostics["signature.state"]);
+        Assert.Equal("valid", verification.Diagnostics.Result);
+        Assert.Null(verification.Diagnostics.FailureReason);
     }
 
     [Fact]
@@ -179,6 +186,8 @@ public sealed class VexAttestationVerifierTests : IDisposable
         Assert.False(verification.IsValid);
         Assert.Equal("error", verification.Diagnostics["signature.state"]);
         Assert.Equal("verification_failed", verification.Diagnostics["signature.reason"]);
+        Assert.Equal("verification_failed", verification.Diagnostics.FailureReason);
+        Assert.Equal("invalid", verification.Diagnostics.Result);
     }
 
     private async Task<(VexAttestationRequest Request, VexAttestationMetadata Metadata, string Envelope)> CreateSignedAttestationAsync(

src/Excititor/__Tests/StellaOps.Excititor.Export.Tests/ExportEngineTests.cs

@@ -6,6 +6,7 @@ using System.Globalization;
 using Microsoft.Extensions.Logging.Abstractions;
 using MongoDB.Driver;
 using StellaOps.Excititor.Core;
+using StellaOps.Excititor.Attestation.Verification;
 using StellaOps.Excititor.Export;
 using StellaOps.Excititor.Policy;
 using StellaOps.Excititor.Storage.Mongo;
@@ -291,7 +292,7 @@ public sealed class ExportEngineTests
         }
 
         public ValueTask<VexAttestationVerification> VerifyAsync(VexAttestationVerificationRequest request, CancellationToken cancellationToken)
-            => ValueTask.FromResult(new VexAttestationVerification(true, ImmutableDictionary<string, string>.Empty));
+            => ValueTask.FromResult(new VexAttestationVerification(true, VexAttestationDiagnostics.Empty));
     }
 
     private sealed class RecordingCacheIndex : IVexCacheIndex

src/Excititor/__Tests/StellaOps.Excititor.WebService.Tests/TestServiceOverrides.cs

@@ -4,13 +4,14 @@ using System.Collections.Immutable;
 using System.Text;
 using System.Text.Json;
 using Microsoft.Extensions.DependencyInjection;
-using Microsoft.Extensions.DependencyInjection.Extensions;
-using Microsoft.Extensions.Hosting;
-using Microsoft.Extensions.Logging;
-using StellaOps.Excititor.Core;
-using StellaOps.Excititor.Export;
-using StellaOps.Excititor.Storage.Mongo;
-using StellaOps.Excititor.WebService.Services;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+using StellaOps.Excititor.Core;
+using StellaOps.Excititor.Attestation.Verification;
+using StellaOps.Excititor.Export;
+using StellaOps.Excititor.Storage.Mongo;
+using StellaOps.Excititor.WebService.Services;
 using MongoDB.Driver;
 using StellaOps.Excititor.Attestation.Dsse;
 
@@ -162,7 +163,7 @@ internal static class TestServiceOverrides
 
         public ValueTask<VexAttestationVerification> VerifyAsync(VexAttestationVerificationRequest request, CancellationToken cancellationToken)
         {
-            var verification = new VexAttestationVerification(true, ImmutableDictionary<string, string>.Empty);
+            var verification = new VexAttestationVerification(true, VexAttestationDiagnostics.Empty);
             return ValueTask.FromResult(verification);
         }
     }

src/Excititor/__Tests/StellaOps.Excititor.Worker.Tests/DefaultVexProviderRunnerTests.cs

@@ -504,6 +504,21 @@ public sealed class DefaultVexProviderRunnerTests
             bool includeGlobal,
             CancellationToken cancellationToken)
             => ValueTask.FromResult(DefaultTrust);
+
+        public ValueTask<IssuerTrustResponseModel> SetIssuerTrustAsync(
+            string tenantId,
+            string issuerId,
+            decimal weight,
+            string? reason,
+            CancellationToken cancellationToken)
+            => ValueTask.FromResult(DefaultTrust);
+
+        public ValueTask DeleteIssuerTrustAsync(
+            string tenantId,
+            string issuerId,
+            string? reason,
+            CancellationToken cancellationToken)
+            => ValueTask.CompletedTask;
     }
 
     private sealed class NoopSignatureVerifier : IVexSignatureVerifier
@@ -655,25 +670,25 @@ public sealed class DefaultVexProviderRunnerTests
         }
     }
 
-    private sealed class StubAttestationVerifier : IVexAttestationVerifier
-    {
-        private readonly bool _isValid;
-        private readonly ImmutableDictionary<string, string> _diagnostics;
-
-        public StubAttestationVerifier(bool isValid, ImmutableDictionary<string, string> diagnostics)
-        {
-            _isValid = isValid;
-            _diagnostics = diagnostics;
-        }
-
-        public int Invocations { get; private set; }
-
-        public ValueTask<VexAttestationVerification> VerifyAsync(VexAttestationVerificationRequest request, CancellationToken cancellationToken)
-        {
-            Invocations++;
-            return ValueTask.FromResult(new VexAttestationVerification(_isValid, _diagnostics));
-        }
-    }
+    private sealed class StubAttestationVerifier : IVexAttestationVerifier
+    {
+        private readonly bool _isValid;
+        private readonly VexAttestationDiagnostics _diagnostics;
+
+        public StubAttestationVerifier(bool isValid, ImmutableDictionary<string, string> diagnostics)
+        {
+            _isValid = isValid;
+            _diagnostics = VexAttestationDiagnostics.FromBuilder(diagnostics.ToBuilder());
+        }
+
+        public int Invocations { get; private set; }
+
+        public ValueTask<VexAttestationVerification> VerifyAsync(VexAttestationVerificationRequest request, CancellationToken cancellationToken)
+        {
+            Invocations++;
+            return ValueTask.FromResult(new VexAttestationVerification(_isValid, _diagnostics));
+        }
+    }
 
     private static VexRawDocument CreateAttestationRawDocument(DateTimeOffset observedAt)
     {

src/Excititor/__Tests/StellaOps.Excititor.Worker.Tests/Signature/WorkerSignatureVerifierTests.cs

@@ -249,19 +249,21 @@ public sealed class WorkerSignatureVerifierTests
     private sealed class StubAttestationVerifier : IVexAttestationVerifier
     {
         private readonly bool _isValid;
-        private readonly ImmutableDictionary<string, string> _diagnostics;
+        private readonly VexAttestationDiagnostics _diagnostics;
 
         public StubAttestationVerifier(bool isValid, ImmutableDictionary<string, string>? diagnostics = null)
-        {
-            _isValid = isValid;
-            _diagnostics = diagnostics ?? ImmutableDictionary<string, string>.Empty;
-        }
-
-        public int Invocations { get; private set; }
-
-        public ValueTask<VexAttestationVerification> VerifyAsync(VexAttestationVerificationRequest request, CancellationToken cancellationToken)
-        {
-            Invocations++;
+        {
+            _isValid = isValid;
+            _diagnostics = diagnostics is null
+                ? VexAttestationDiagnostics.Empty
+                : VexAttestationDiagnostics.FromBuilder(diagnostics.ToBuilder());
+        }
+
+        public int Invocations { get; private set; }
+
+        public ValueTask<VexAttestationVerification> VerifyAsync(VexAttestationVerificationRequest request, CancellationToken cancellationToken)
+        {
+            Invocations++;
             return ValueTask.FromResult(new VexAttestationVerification(_isValid, _diagnostics));
         }
     }
@@ -269,7 +271,7 @@ public sealed class WorkerSignatureVerifierTests
     private sealed class StubIssuerDirectoryClient : IIssuerDirectoryClient
     {
         private readonly IReadOnlyList<IssuerKeyModel> _keys;
-        private readonly IssuerTrustResponseModel _trust;
+        private IssuerTrustResponseModel _trust;
 
         private StubIssuerDirectoryClient(
             IReadOnlyList<IssuerKeyModel> keys,
@@ -302,7 +304,7 @@ public sealed class WorkerSignatureVerifierTests
                 null,
                 null);
 
-            var now = DateTimeOffset.UtcNow;
+            var now = DateTimeOffset.UnixEpoch;
             var overrideModel = new IssuerTrustOverrideModel(weight, "stub", now, "test", now, "test");
             return new StubIssuerDirectoryClient(
                 new[] { key },
@@ -322,6 +324,29 @@ public sealed class WorkerSignatureVerifierTests
             bool includeGlobal,
             CancellationToken cancellationToken)
             => ValueTask.FromResult(_trust);
+
+        public ValueTask<IssuerTrustResponseModel> SetIssuerTrustAsync(
+            string tenantId,
+            string issuerId,
+            decimal weight,
+            string? reason,
+            CancellationToken cancellationToken)
+        {
+            var now = DateTimeOffset.UnixEpoch;
+            var overrideModel = new IssuerTrustOverrideModel(weight, "stub-set", now, "test", now, "test");
+            _trust = new IssuerTrustResponseModel(overrideModel, null, weight);
+            return ValueTask.FromResult(_trust);
+        }
+
+        public ValueTask DeleteIssuerTrustAsync(
+            string tenantId,
+            string issuerId,
+            string? reason,
+            CancellationToken cancellationToken)
+        {
+            _trust = new IssuerTrustResponseModel(null, null, 0m);
+            return ValueTask.CompletedTask;
+        }
     }
 
     private sealed class FixedTimeProvider : TimeProvider