diff --git a/frontend-modern/src/utils/__tests__/availabilityProbePresentation.branchcov0719.test.ts b/frontend-modern/src/utils/__tests__/availabilityProbePresentation.branchcov0719.test.ts
new file mode 100644
index 000000000..4394555b3
--- /dev/null
+++ b/frontend-modern/src/utils/__tests__/availabilityProbePresentation.branchcov0719.test.ts
@@ -0,0 +1,542 @@
+import { afterEach, describe, expect, it, vi } from 'vitest';
+import type { Resource, ResourceAvailabilityMeta } from '@/types/resource';
+import {
+  getAvailabilityProbeEndpointLabel,
+  getAvailabilityProbePresentation,
+} from '@/utils/availabilityProbePresentation';
+
+// Residual branch-coverage probes for availabilityProbePresentation.
+//
+// The sibling tests (availabilityProbePresentation.test.ts and
+// availabilityProbePresentation.branchcov2.test.ts) already pin the canonical
+// arms of the exported helpers (method/target/result/tone/failureCount and
+// the presentation assembly). This file targets the *residual* arms they
+// never trip:
+//   - `getAvailabilityProbeEndpointLabel` is 0% covered and is the primary
+//     target here — every address/port/protocol/path arm is driven directly.
+//   - `getAvailabilityCorrelationLabel`, `getAvailabilityFreshnessLabel`,
+//     `getAvailabilityProbeToneClassName`, and the 5xx branch of the
+//     private result-label helper are exercised indirectly through the
+//     assembled presentation, mirroring the sibling test's pattern.
+
+const makeAvailability = (
+  overrides?: Partial<ResourceAvailabilityMeta>,
+): ResourceAvailabilityMeta => ({
+  protocol: 'tcp',
+  port: 443,
+  available: true,
+  latencyMillis: 5,
+  lastChecked: '2026-05-06T13:00:00Z',
+  ...overrides,
+});
+
+const makeResource = (overrides?: Partial<Resource>): Resource => ({
+  id: 'availability:probe-endpoint',
+  type: 'network-endpoint',
+  name: 'probe-target',
+  displayName: 'probe-target',
+  platformId: 'probe-endpoint',
+  platformType: 'availability',
+  sourceType: 'api',
+  status: 'online',
+  lastSeen: 1,
+  availability: makeAvailability(),
+  platformData: { sources: ['availability'] },
+  ...overrides,
+});
+
+const AT = new Date('2026-05-06T13:00:20Z').getTime();
+
+describe('getAvailabilityProbeEndpointLabel — branch coverage (primary target)', () => {
+  // The helper is:
+  //   address = (availability?.address ?? '').trim()
+  //   addressWithPort = address && isFinitePort(port) && !address.endsWith(`:${port}`)
+  //                    ? `${address}:${port}` : address
+  //   if (http(s) && availability.path) {
+  //     path = path.trim()
+  //     if (path && !addressWithPort.endsWith(path)) {
+  //       return addressWithPort.replace(/\/+$/, '') + (path startsWith '/' ? path : `/${path}`)
+  //     }
+  //   }
+  //   return addressWithPort
+
+  describe('nullish / empty fallbacks', () => {
+    it('returns an empty string when availability is undefined', () => {
+      expect(getAvailabilityProbeEndpointLabel(undefined)).toBe('');
+    });
+
+    it('returns an empty string when availability is null', () => {
+      expect(getAvailabilityProbeEndpointLabel(null)).toBe('');
+    });
+
+    it('returns an empty string when no address is set', () => {
+      expect(getAvailabilityProbeEndpointLabel({ protocol: 'tcp', port: 443 })).toBe('');
+    });
+
+    it('returns an empty string when address is whitespace-only (trimmed to empty)', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: '   ' })).toBe('');
+    });
+  });
+
+  describe('addressWithPort — port-append arm (truthy branch of the ternary)', () => {
+    it('appends a positive finite port to a bare address', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: '10.0.0.1', port: 443 })).toBe(
+        '10.0.0.1:443',
+      );
+    });
+
+    it('appends a port even when the protocol is unrecognized (protocol is orthogonal)', () => {
+      expect(
+        getAvailabilityProbeEndpointLabel({ address: 'host.local', protocol: 'snmp', port: 161 }),
+      ).toBe('host.local:161');
+    });
+
+    it('trims surrounding whitespace from the address before appending the port', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: '  10.0.0.2  ', port: 22 })).toBe(
+        '10.0.0.2:22',
+      );
+    });
+  });
+
+  describe('addressWithPort — fallback arm (falsy branch of the ternary)', () => {
+    it('returns the bare address when port is missing', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: 'example.com' })).toBe('example.com');
+    });
+
+    it('returns the bare address when port is 0 (port > 0 guard)', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: 'example.com', port: 0 })).toBe(
+        'example.com',
+      );
+    });
+
+    it('returns the bare address when port is negative', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: 'example.com', port: -1 })).toBe(
+        'example.com',
+      );
+    });
+
+    it('returns the bare address when port is non-finite (Infinity)', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: 'example.com', port: Infinity })).toBe(
+        'example.com',
+      );
+    });
+
+    it('returns the bare address when port is non-finite (NaN)', () => {
+      expect(getAvailabilityProbeEndpointLabel({ address: 'example.com', port: NaN })).toBe(
+        'example.com',
+      );
+    });
+
+    it('returns the bare address when port is the wrong type (string)', () => {
+      expect(
+        getAvailabilityProbeEndpointLabel({ address: 'example.com', port: 'abc' as unknown as number }),
+      ).toBe('example.com');
+    });
+
+    it('does not duplicate the port when the address already ends with ":<port>"', () => {
+      // The `!address.endsWith(`:${port}`)` guard prevents `host:443:443`.
+      expect(getAvailabilityProbeEndpointLabel({ address: 'example.com:443', port: 443 })).toBe(
+        'example.com:443',
+      );
+    });
+  });
+
+  describe('http(s) path-append arm', () => {
+    it('appends an absolute path to an http address with a port', () => {
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: '10.0.0.5',
+          protocol: 'http',
+          port: 8080,
+          path: '/healthz',
+        }),
+      ).toBe('10.0.0.5:8080/healthz');
+    });
+
+    it('appends an absolute path to an https address with no port', () => {
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: 'api.example.com',
+          protocol: 'https',
+          path: '/v1/status',
+        }),
+      ).toBe('api.example.com/v1/status');
+    });
+
+    it('prepends a leading "/" when the stored path does not start with one', () => {
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: 'api.example.com',
+          protocol: 'https',
+          path: 'ready',
+        }),
+      ).toBe('api.example.com/ready');
+    });
+
+    it('strips trailing slashes from the address before appending the path', () => {
+      // `addressWithPort.replace(/\/+$/, '')` — `host//` -> `host` before path join.
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: 'api.example.com//',
+          protocol: 'https',
+          path: '/status',
+        }),
+      ).toBe('api.example.com/status');
+    });
+
+    it('falls through when the path is whitespace-only (trim() yields empty)', () => {
+      // The inner `if (path && ...)` guard — whitespace path is treated as no path.
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: 'api.example.com',
+          protocol: 'https',
+          path: '   ',
+        }),
+      ).toBe('api.example.com');
+    });
+
+    it('does not re-append the path when addressWithPort already ends with it', () => {
+      // The `!addressWithPort.endsWith(path)` guard prevents `host/status/status`.
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: 'api.example.com/status',
+          protocol: 'https',
+          path: '/status',
+        }),
+      ).toBe('api.example.com/status');
+    });
+
+    it('still appends the port to an http address before joining the path', () => {
+      // Combined arm: port-append + path-append + path-starts-with-/ branch.
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: '10.0.0.9',
+          protocol: 'http',
+          port: 5000,
+          path: '/ready',
+        }),
+      ).toBe('10.0.0.9:5000/ready');
+    });
+
+    it('does not join the path for a non-http(s) protocol even when a path is set', () => {
+      // The `(protocol === 'http' || protocol === 'https')` guard — tcp path is ignored.
+      expect(
+        getAvailabilityProbeEndpointLabel({
+          address: '10.0.0.9',
+          protocol: 'tcp',
+          port: 5432,
+          path: '/should-be-ignored',
+        }),
+      ).toBe('10.0.0.9:5432');
+    });
+  });
+});
+
+describe('getAvailabilityCorrelationLabel — residual arms (via presentation.correlationLabel)', () => {
+  afterEach(() => vi.restoreAllMocks());
+
+  it('renders "Resource link is unresolved" for the "unresolved" correlation state', () => {
+    vi.spyOn(Date, 'now').mockReturnValue(AT);
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({ correlationState: 'unresolved' }),
+      }),
+    );
+    expect(presentation?.correlationLabel).toBe('Resource link is unresolved');
+    expect(presentation?.detailLabel).toContain('Resource link is unresolved');
+  });
+
+  it('renders "Standalone endpoint" for the "standalone" correlation state', () => {
+    vi.spyOn(Date, 'now').mockReturnValue(AT);
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({ correlationState: 'standalone' }),
+      }),
+    );
+    expect(presentation?.correlationLabel).toBe('Standalone endpoint');
+    expect(presentation?.detailLabel).toContain('Standalone endpoint');
+  });
+
+  it('collapses ambiguous-with-exactly-one-candidate to the generic ambiguous label', () => {
+    // `correlationCandidates > 1` is false at the boundary value of 1.
+    vi.spyOn(Date, 'now').mockReturnValue(AT);
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({ correlationState: 'ambiguous', correlationCandidates: 1 }),
+      }),
+    );
+    expect(presentation?.correlationLabel).toBe('Resource match is ambiguous');
+    expect(presentation?.detailLabel).not.toContain('possible resource matches');
+  });
+
+  it('collapses ambiguous-with-no-candidates to the generic ambiguous label', () => {
+    // `availability.correlationCandidates && ...` is falsy when the field is absent.
+    vi.spyOn(Date, 'now').mockReturnValue(AT);
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({ correlationState: 'ambiguous' }),
+      }),
+    );
+    expect(presentation?.correlationLabel).toBe('Resource match is ambiguous');
+  });
+
+  it('returns a null correlation label for the default switch arm (no correlation state)', () => {
+    vi.spyOn(Date, 'now').mockReturnValue(AT);
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({ correlationState: undefined }),
+      }),
+    );
+    expect(presentation?.correlationLabel).toBeNull();
+  });
+
+  it('returns a null correlation label for the "attached" correlation state', () => {
+    // `attached` is on the union but has no case clause, so it falls to `default`.
+    vi.spyOn(Date, 'now').mockReturnValue(AT);
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({ correlationState: 'attached' }),
+      }),
+    );
+    expect(presentation?.correlationLabel).toBeNull();
+  });
+});
+
+describe('getAvailabilityFreshnessLabel — residual arms (via presentation.freshnessLabel)', () => {
+  afterEach(() => vi.restoreAllMocks());
+
+  it('reports "fresh" when evidence.validUntil is at or after now (>= boundary)', () => {
+    const now = new Date('2026-05-06T13:00:00Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          evidence: {
+            id: 'evidence-fresh',
+            source: { provider: 'availability', collector: 'availability-poller' },
+            subject: { resourceId: 'availability:probe-endpoint' },
+            observedAt: '2026-05-06T12:55:00Z',
+            ingestedAt: '2026-05-06T12:55:00Z',
+            validUntil: '2026-05-06T13:00:00Z',
+            completeness: 'complete',
+            confidence: 'confirmed',
+            permissions: 'sufficient',
+          },
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('fresh');
+  });
+
+  it('reports "fresh" via lastChecked + pollIntervalSeconds when within 2x the interval', () => {
+    // checked 10s ago, pollInterval 30s -> 10 + 30*2 = 70s ahead of now -> fresh.
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: 30,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('fresh');
+  });
+
+  it('reports "stale" via lastChecked + pollIntervalSeconds when past 2x the interval', () => {
+    // checked 10s ago, pollInterval 2s -> 10 + 2*2 = 4s ahead, but now is past it -> stale.
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: 2,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('stale');
+  });
+
+  it('falls through to the pollInterval arm when evidence.validUntil is unparseable', () => {
+    // validUntil exists but Date.parse yields NaN; lastChecked+pollInterval still says fresh.
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: 30,
+          evidence: {
+            id: 'evidence-bad',
+            source: { provider: 'availability', collector: 'availability-poller' },
+            subject: { resourceId: 'availability:probe-endpoint' },
+            observedAt: '2026-05-06T12:55:00Z',
+            ingestedAt: '2026-05-06T12:55:00Z',
+            validUntil: 'not-a-real-date',
+            completeness: 'complete',
+            confidence: 'confirmed',
+            permissions: 'sufficient',
+          },
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('fresh');
+  });
+
+  it('reports "freshness unknown" when lastChecked is missing and no validUntil', () => {
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: undefined,
+          pollIntervalSeconds: 30,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('freshness unknown');
+  });
+
+  it('reports "freshness unknown" when lastChecked is unparseable', () => {
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: 'not-a-real-date',
+          pollIntervalSeconds: 30,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('freshness unknown');
+  });
+
+  it('reports "freshness unknown" when pollIntervalSeconds is missing', () => {
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: undefined,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('freshness unknown');
+  });
+
+  it('reports "freshness unknown" when pollIntervalSeconds is zero (<= 0 guard)', () => {
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: 0,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('freshness unknown');
+  });
+
+  it('reports "freshness unknown" when pollIntervalSeconds is negative (<= 0 guard)', () => {
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: -5,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('freshness unknown');
+  });
+
+  it('reports "freshness unknown" when pollIntervalSeconds is non-finite', () => {
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: Infinity,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('freshness unknown');
+  });
+
+  it('reports "freshness unknown" when pollIntervalSeconds is the wrong type', () => {
+    const now = new Date('2026-05-06T13:00:10Z');
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        availability: makeAvailability({
+          lastChecked: '2026-05-06T13:00:00Z',
+          pollIntervalSeconds: 'soon' as unknown as number,
+        }),
+      }),
+      now,
+    );
+    expect(presentation?.freshnessLabel).toBe('freshness unknown');
+  });
+});
+
+describe('getAvailabilityProbeToneClassName — residual warning arm (via presentation.toneClassName)', () => {
+  afterEach(() => vi.restoreAllMocks());
+
+  it('returns the warning class for the "unresolved" correlation state', () => {
+    // Neither hard-failed nor degraded nor stale, but correlationState === 'unresolved'
+    // is one of the ||'d warning triggers the sibling tests never trip.
+    vi.spyOn(Date, 'now').mockReturnValue(AT);
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        status: 'online',
+        availability: makeAvailability({
+          available: true,
+          latencyMillis: 5,
+          lastChecked: '2026-05-06T13:00:00Z',
+          correlationState: 'unresolved',
+        }),
+      }),
+    );
+    expect(presentation?.toneClassName).toBe('text-amber-600 dark:text-amber-300');
+  });
+});
+
+describe('getAvailabilityProbeResultLabel — residual 5xx status arm (via presentation.resultLabel)', () => {
+  afterEach(() => vi.restoreAllMocks());
+
+  it('extracts a 5xx HTTP status code from lastError', () => {
+    // The sibling test covers the 4xx (404) arm; this pins the `[45]\d{2}` 5xx arm.
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        status: 'online',
+        availability: {
+          protocol: 'http',
+          available: false,
+          lastChecked: '2026-05-06T13:00:00Z',
+          lastError: 'upstream returned 503 Service Unavailable',
+        },
+      }),
+    );
+    expect(presentation?.resultLabel).toBe('503');
+  });
+
+  it('extracts a 5xx HTTP status code that appears at the start of lastError', () => {
+    // Word-boundary regex `\b([45]\d{2})\b` — confirm it matches at offset 0.
+    const presentation = getAvailabilityProbePresentation(
+      makeResource({
+        status: 'online',
+        availability: {
+          protocol: 'http',
+          available: false,
+          lastChecked: '2026-05-06T13:00:00Z',
+          lastError: '500 Internal Server Error',
+        },
+      }),
+    );
+    expect(presentation?.resultLabel).toBe('500');
+  });
+});