From 2f5c508b33e3fd1b5b6d081ede1d34219320e90c Mon Sep 17 00:00:00 2001
From: Trae AI <trae-ai@example.local>
Date: Tue, 26 May 2026 01:31:05 +0800
Subject: [PATCH] Add evolver error corrector

---
 gitnexus/src/core/evolver/error-corrector.ts  | 34 ++++++++++
 gitnexus/src/core/evolver/index.ts            |  1 +
 .../test/unit/evolver/error-corrector.test.ts | 66 +++++++++++++++++++
 3 files changed, 101 insertions(+)
 create mode 100644 gitnexus/src/core/evolver/error-corrector.ts
 create mode 100644 gitnexus/test/unit/evolver/error-corrector.test.ts

diff --git a/gitnexus/src/core/evolver/error-corrector.ts b/gitnexus/src/core/evolver/error-corrector.ts
new file mode 100644
index 000000000..a6a2bbe8b
--- /dev/null
+++ b/gitnexus/src/core/evolver/error-corrector.ts
@@ -0,0 +1,34 @@
+import type { CorrectionAction, CorrectionActionType, ErrorEvent } from './types.js';
+
+const createdAt = '2026-05-25T00:00:00.000Z';
+
+const ERROR_ACTION_MAP: Record<ErrorEvent['type'], CorrectionActionType> = {
+  'temporary-failure': 'retry',
+  'parameter-degradation': 'rollback-parameters',
+  'algorithm-regression': 'disable-variant',
+  'structure-risk': 'request-structure-review',
+  'resource-exhaustion': 'reduce-budget',
+  'evaluation-distortion': 'freeze-promotion',
+  'safety-boundary-triggered': 'stop-plan',
+};
+
+const ERROR_REASON_MAP: Record<ErrorEvent['type'], string> = {
+  'temporary-failure': 'temporary failure may succeed on retry',
+  'parameter-degradation': 'parameter change caused degradation, rollback required',
+  'algorithm-regression': 'algorithm change caused regression, variant must be disabled',
+  'structure-risk': 'structure change poses risk, manual review required',
+  'resource-exhaustion': 'resource limits exceeded, budget must be reduced',
+  'evaluation-distortion': 'evaluation results are unreliable, promotion must be frozen',
+  'safety-boundary-triggered': 'safety boundary violated, plan must be stopped',
+};
+
+export function selectCorrectionAction(errorEvent: ErrorEvent): CorrectionAction {
+  return {
+    id: `correction-${errorEvent.id}`,
+    errorEventId: errorEvent.id,
+    type: ERROR_ACTION_MAP[errorEvent.type],
+    reason: ERROR_REASON_MAP[errorEvent.type],
+    createdAt,
+    variantId: errorEvent.variantId,
+  };
+}
diff --git a/gitnexus/src/core/evolver/index.ts b/gitnexus/src/core/evolver/index.ts
index e4958c92f..5b4dc683d 100644
--- a/gitnexus/src/core/evolver/index.ts
+++ b/gitnexus/src/core/evolver/index.ts
@@ -6,3 +6,4 @@ export * from './sandbox-runner.js';
 export * from './safety-gate.js';
 export * from './promotion-controller.js';
 export * from './evolution-memory.js';
+export * from './error-corrector.js';
diff --git a/gitnexus/test/unit/evolver/error-corrector.test.ts b/gitnexus/test/unit/evolver/error-corrector.test.ts
new file mode 100644
index 000000000..1528fd3d6
--- /dev/null
+++ b/gitnexus/test/unit/evolver/error-corrector.test.ts
@@ -0,0 +1,66 @@
+import { describe, expect, it } from 'vitest';
+import { selectCorrectionAction } from '../../../src/core/evolver/index.js';
+import type { ErrorEvent } from '../../../src/core/evolver/index.js';
+
+const occurredAt = '2026-05-25T00:00:00.000Z';
+
+function errorEvent(type: ErrorEvent['type'], variantId = 'variant-1'): ErrorEvent {
+  return {
+    id: `error-${type}`,
+    type,
+    message: `${type} occurred`,
+    occurredAt,
+    variantId,
+  };
+}
+
+describe('selectCorrectionAction', () => {
+  it('maps temporary-failure to retry', () => {
+    const action = selectCorrectionAction(errorEvent('temporary-failure'));
+    expect(action).toEqual({
+      id: `correction-error-temporary-failure`,
+      errorEventId: 'error-temporary-failure',
+      type: 'retry',
+      reason: 'temporary failure may succeed on retry',
+      createdAt: occurredAt,
+      variantId: 'variant-1',
+    });
+  });
+
+  it('maps parameter-degradation to rollback-parameters', () => {
+    const action = selectCorrectionAction(errorEvent('parameter-degradation'));
+    expect(action.type).toBe('rollback-parameters');
+    expect(action.errorEventId).toBe('error-parameter-degradation');
+    expect(action.variantId).toBe('variant-1');
+  });
+
+  it('maps algorithm-regression to disable-variant', () => {
+    const action = selectCorrectionAction(errorEvent('algorithm-regression'));
+    expect(action.type).toBe('disable-variant');
+    expect(action.errorEventId).toBe('error-algorithm-regression');
+  });
+
+  it('maps structure-risk to request-structure-review', () => {
+    const action = selectCorrectionAction(errorEvent('structure-risk'));
+    expect(action.type).toBe('request-structure-review');
+    expect(action.errorEventId).toBe('error-structure-risk');
+  });
+
+  it('maps resource-exhaustion to reduce-budget', () => {
+    const action = selectCorrectionAction(errorEvent('resource-exhaustion'));
+    expect(action.type).toBe('reduce-budget');
+    expect(action.errorEventId).toBe('error-resource-exhaustion');
+  });
+
+  it('maps evaluation-distortion to freeze-promotion', () => {
+    const action = selectCorrectionAction(errorEvent('evaluation-distortion'));
+    expect(action.type).toBe('freeze-promotion');
+    expect(action.errorEventId).toBe('error-evaluation-distortion');
+  });
+
+  it('maps safety-boundary-triggered to stop-plan', () => {
+    const action = selectCorrectionAction(errorEvent('safety-boundary-triggered'));
+    expect(action.type).toBe('stop-plan');
+    expect(action.errorEventId).toBe('error-safety-boundary-triggered');
+  });
+});