Q134: a signal's category comes from its runtime source, so self-checks cannot pass as real traffic

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/main/database/migrations/097-drop-drill-only-slo.ts

@@ -0,0 +1,7 @@
+// The browser-session SLO was fed only by the removed chaos drill, so no runtime signal could ever meet or miss it.
+export const dropDrillOnlySloSchema = `
+  delete from slo_targets where signal_key = 'browser_session_boundary';
+
+  insert into schema_migrations(version, name, applied_at)
+  values (97, 'drop_drill_only_slo', datetime('now'));
+`;

src/main/database/schema.ts

@@ -95,6 +95,7 @@ import { taskEnqueueErrorSchema } from "./migrations/093-task-enqueue-error";
 import { dropConfigCountEvalsSchema } from "./migrations/094-drop-config-count-evals";
 import { dropPrBotGatesSchema } from "./migrations/095-drop-pr-bot-gates";
 import { dropChaosDrillsSchema } from "./migrations/096-drop-chaos-drills";
+import { dropDrillOnlySloSchema } from "./migrations/097-drop-drill-only-slo";
 
 interface Migration {
   version: number;
@@ -199,6 +200,7 @@ const MIGRATIONS: Migration[] = [
   { version: 94, name: "drop_config_count_evals", sql: dropConfigCountEvalsSchema },
   { version: 95, name: "drop_pr_bot_gates", sql: dropPrBotGatesSchema },
   { version: 96, name: "drop_chaos_drills", sql: dropChaosDrillsSchema },
+  { version: 97, name: "drop_drill_only_slo", sql: dropDrillOnlySloSchema },
 ];
 
 const SCHEMA_VERSION = MIGRATIONS[MIGRATIONS.length - 1].version;

src/main/services/migration-service.ts

@@ -3,7 +3,6 @@ import { createHash } from "node:crypto";
 import { resolve } from "node:path";
 import { DatabaseSync, type StatementSync } from "node:sqlite";
 import type { CreateMigrationReportInput } from "../../shared/commands";
-import { SLO_SIGNAL_KEY } from "../../shared/domain";
 import { createId } from "../../shared/ids";
 import { AuditService } from "./audit-service";
 import { buildMigrationValidationSummary, type MigrationValidationSummary } from "./migration-validation-summary";
@@ -343,7 +342,6 @@ export class MigrationService {
       });
       this.operations.recordSignal({
         orgId: input.orgId,
-        signalKey: SLO_SIGNAL_KEY.MIGRATION_VALIDATION_SUCCESS,
         source: "migration_validation",
         success: validationSummary.passed,
         durationMs: null,

src/main/services/operations-service.ts

@@ -1,6 +1,6 @@
 import type { DatabaseSync } from "node:sqlite";
 import type { SetFeatureFlagInput } from "../../shared/commands";
-import { FEATURE_FLAG_KEY, SLO_SIGNAL_KEY, type FeatureFlagKey, type SloSignalKey } from "../../shared/domain";
+import { FEATURE_FLAG_KEY, SLO_SIGNAL_KEY, type FeatureFlagKey } from "../../shared/domain";
 import { createId } from "../../shared/ids";
 import { AuditService } from "./audit-service";
 
@@ -10,10 +10,18 @@ const FEATURE_FLAGS = [
   { key: FEATURE_FLAG_KEY.BOARD_INTERVENTION, label: "Board intervention", enabled: true },
 ] as const;
 
+/** Each runtime source and the one signal it reports; drills and self-checks have no source here, so they cannot pass as real traffic. */
+const SIGNAL_OF_SOURCE = {
+  provider_gateway: SLO_SIGNAL_KEY.PROVIDER_REQUEST_SUCCESS,
+  approval_routing: SLO_SIGNAL_KEY.APPROVAL_ROUTE_COVERAGE,
+  skill_resolver: SLO_SIGNAL_KEY.SKILL_RESOLVE_SUCCESS,
+  migration_validation: SLO_SIGNAL_KEY.MIGRATION_VALIDATION_SUCCESS,
+} as const;
+export type SignalSource = keyof typeof SIGNAL_OF_SOURCE;
+
 const SLO_TARGETS = [
   { signalKey: SLO_SIGNAL_KEY.PROVIDER_REQUEST_SUCCESS, label: "Provider requests", targetBasisPoints: 9950, windowMinutes: 43200 },
   { signalKey: SLO_SIGNAL_KEY.APPROVAL_ROUTE_COVERAGE, label: "Approval routing", targetBasisPoints: 10000, windowMinutes: 43200 },
-  { signalKey: SLO_SIGNAL_KEY.BROWSER_SESSION_BOUNDARY, label: "Browser session boundary", targetBasisPoints: 10000, windowMinutes: 43200 },
   { signalKey: SLO_SIGNAL_KEY.SKILL_RESOLVE_SUCCESS, label: "Skill resolve", targetBasisPoints: 9950, windowMinutes: 43200 },
   { signalKey: SLO_SIGNAL_KEY.MIGRATION_VALIDATION_SUCCESS, label: "Migration validation", targetBasisPoints: 10000, windowMinutes: 43200 },
 ] as const;
@@ -68,21 +76,15 @@ export class OperationsService {
     return row.enabled === 1;
   }
 
-  recordSignal(input: {
-    orgId: string;
-    signalKey: SloSignalKey;
-    source: string;
-    success: boolean;
-    durationMs: number | null;
-    detail: unknown;
-  }): void {
+  recordSignal(input: { orgId: string; source: SignalSource; success: boolean; durationMs: number | null; detail: unknown }): void {
+    if (!Object.hasOwn(SIGNAL_OF_SOURCE, input.source)) throw new Error(`"${input.source}" is not a runtime signal source.`);
     this.db.prepare(`
       insert into operational_events(id, org_id, signal_key, source, success, duration_ms, detail_json, created_at)
       values (?, ?, ?, ?, ?, ?, ?, ?)
     `).run(
       createId("ope"),
       input.orgId,
-      input.signalKey,
+      SIGNAL_OF_SOURCE[input.source],
       input.source,
       input.success ? 1 : 0,
       input.durationMs,

src/main/services/org-governance-service.ts

@@ -1,6 +1,6 @@
 import type { DatabaseSync } from "node:sqlite";
 import type { CreateAgentInput } from "../../shared/commands";
-import { RISK_LEVEL, ROUTE_TO_TYPE, SLO_SIGNAL_KEY, type RiskLevel } from "../../shared/domain";
+import { RISK_LEVEL, ROUTE_TO_TYPE, type RiskLevel } from "../../shared/domain";
 import { createId } from "../../shared/ids";
 import { AuditService } from "./audit-service";
 import { OperationsService } from "./operations-service";
@@ -117,7 +117,6 @@ export class OrgGovernanceService {
     });
     this.operations.recordSignal({
       orgId: input.orgId,
-      signalKey: SLO_SIGNAL_KEY.APPROVAL_ROUTE_COVERAGE,
       source: "approval_routing",
       success: true,
       durationMs: null,

src/main/services/provider-response-observer.ts

@@ -1,5 +1,5 @@
 import type { DatabaseSync } from "node:sqlite";
-import { SLO_SIGNAL_KEY, type ProviderExecutionMode } from "../../shared/domain";
+import type { ProviderExecutionMode } from "../../shared/domain";
 import type { ProviderObservedRateLimitState } from "../../shared/provider-runtime-domain";
 import { AuditService } from "./audit-service";
 import { OperationsService } from "./operations-service";
@@ -59,7 +59,6 @@ export class ProviderResponseObserver {
     });
     this.operations.recordSignal({
       orgId: input.orgId,
-      signalKey: SLO_SIGNAL_KEY.PROVIDER_REQUEST_SUCCESS,
       source: "provider_gateway",
       success: true,
       durationMs: Date.now() - input.startedAt,
@@ -85,7 +84,6 @@ export class ProviderResponseObserver {
     this.recordProviderHealth(input.provider.id, input.orgId, HEALTH_STATE_FAILED, message);
     this.operations.recordSignal({
       orgId: input.orgId,
-      signalKey: SLO_SIGNAL_KEY.PROVIDER_REQUEST_SUCCESS,
       source: "provider_gateway",
       success: false,
       durationMs: Date.now() - input.startedAt,

src/main/services/skill-service.ts

@@ -1,7 +1,6 @@
 import { existsSync, readFileSync } from "node:fs";
 import type { DatabaseSync } from "node:sqlite";
 import type { BindSkillInput, ImportSkillDirectoryInput, ResolveAgentSkillsInput, RunSkillTestsInput } from "../../shared/commands";
-import { SLO_SIGNAL_KEY } from "../../shared/domain";
 import { createId } from "../../shared/ids";
 import { AuditService } from "./audit-service";
 import { OperationsService } from "./operations-service";
@@ -390,7 +389,6 @@ export class SkillService {
     });
     this.operations.recordSignal({
       orgId: input.orgId,
-      signalKey: SLO_SIGNAL_KEY.SKILL_RESOLVE_SUCCESS,
       source: "skill_resolver",
       success: true,
       durationMs: null,