Shift Left Testing

Name: Shift Left Testing
Author: proffesor-for-testing

proffesor-for-testing/agentic-qe

94 installs
433 repo stars
Updated August 4, 2026
proffesor-for-testing/agentic-qe

shift-left-testing is a Claude Code skill for testing & qa.

About

shift-left-testing is a Claude Code skill for testing & qa. It helps solo builders move faster with AI-assisted development.

shift-left-testing
Testing & QA
AI-coding skill

Shift Left Testing by the numbers

94 all-time installs (skills.sh)
+3 installs in the week ending Aug 4, 2026 (Skillselion tracking)
Ranked #1,019 of 2,153 Testing & QA skills by installs in the Skillselion catalog
Data as of Aug 5, 2026 (Skillselion catalog sync)

npx skills add https://github.com/proffesor-for-testing/agentic-qe --skill shift-left-testing

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Installs	94
repo stars	★ 433
Last updated	August 4, 2026
Repository	proffesor-for-testing/agentic-qe ↗

How do I helps with testing & qa tasks.?

Helps with testing & qa tasks.

Who is it for?

Best when you're working on testing & qa and need structured help with shift left testing.

Skip if: Teams with no testing & qa needs, or anyone wanting a generic chat assistant without this specific workflow.

When should I use this skill?

When you need to helps with testing & qa tasks., or when shift-left-testing is a claude code skill for testing & qa.

What you get

Structured output aligned to shift-left-testing: shift-left-testing, Testing & QA.

Files

SKILL.mdMarkdownGitHub ↗

Shift-Left Testing

<default_to_action> When implementing early testing practices: 1. VALIDATE requirements before coding (testability, BDD scenarios) 2. WRITE tests before implementation (TDD) 3. AUTOMATE in CI pipeline (every commit triggers tests) 4. FIX defects immediately - never let them accumulate

Quick Shift-Left Levels:

Level 1: Unit tests with each PR (developer responsibility)
Level 2: TDD practice (tests before code)
Level 3: BDD/Example mapping in refinement (requirements testing)
Level 4: Risk analysis in design (architecture testing)

</default_to_action>

Quick Reference Card

When to Use

Reducing cost of defects
Implementing CI/CD pipelines
Starting TDD practice
Improving requirements quality

Shift-Left Levels

Level	Practice	When
1	Unit tests in PR	Before merge
2	TDD	Before implementation
3	BDD/Example Mapping	During refinement
4	Risk Analysis	During design

---

Level 1: Tests in Every PR

# CI pipeline - tests run on every commit
name: CI
on: [push, pull_request]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: npm ci
      - run: npm run test:unit
      - run: npm run test:integration
      - run: npm run lint

  quality-gate:
    needs: test
    steps:
      - name: Coverage Check
        run: npx coverage-check --min 80
      - name: No New Warnings
        run: npm run lint -- --max-warnings 0

---

Agent-Assisted Shift-Left

// Validate requirements testability
await Task("Requirements Validation", {
  requirements: userStories,
  check: ['INVEST-criteria', 'testability', 'ambiguity'],
  generateBDD: true
}, "qe-requirements-validator");

// Generate tests from requirements
await Task("Generate Tests", {
  source: 'requirements',
  types: ['unit', 'integration', 'e2e'],
  coverage: 'comprehensive'
}, "qe-test-generator");

// Smart test selection for changes
await Task("Select Regression Tests", {
  changedFiles: prFiles,
  algorithm: 'risk-based',
  targetReduction: 0.7  // 70% time savings
}, "qe-regression-risk-analyzer");

---

Agent Coordination Hints

Memory Namespace

aqe/shift-left/
├── requirements/*       - Validated requirements
├── generated-tests/*    - Auto-generated tests
├── coverage-targets/*   - Coverage goals by component
└── pipeline-results/*   - CI/CD test history

Fleet Coordination

const shiftLeftFleet = await FleetManager.coordinate({
  strategy: 'shift-left',
  agents: [
    'qe-requirements-validator',     // Level 3-4
    'qe-test-generator',             // Level 2
    'qe-regression-risk-analyzer'    // Smart selection
  ],
  topology: 'sequential'
});

---

Related Skills

tdd-london-chicago - TDD practices
holistic-testing-pact - Proactive testing
cicd-pipeline-qe-orchestrator - Pipeline integration
shift-right-testing - Production feedback

---

Remember

With Agents: Agents validate requirements testability, generate tests from specs, and select optimal regression suites. Use agents to implement shift-left practices consistently.

Skill Composition

TDD practice → Use /tdd-london-chicago for specific TDD guidance
Generate tests → Use /qe-test-generation for AI-powered test generation
CI/CD quality → Use /cicd-pipeline-qe-orchestrator for pipeline setup

Gotchas

"Shift left" doesn't mean "only test left" — production monitoring (shift right) is still needed
Agent generates tests before understanding requirements — tests for wrong behavior are worse than no tests
CI pipeline tests that take >10 minutes kill the feedback loop — keep commit-stage tests under 5 minutes
TDD discipline degrades when agent writes test+code simultaneously — enforce Red phase separation
Shifting left without lightweight environments just shifts the bottleneck — fix environments first

skill: shift-left-testing
version: 1.0.0
description: >
  Evaluation suite for shift-left testing strategy.
  Tests early defect detection, pre-commit checks, and development-phase validation.

models_to_test:
  - claude-sonnet-4-6    # Primary (high accuracy expected)
  - claude-haiku-4-5     # Fast model (minimum quality floor)

mcp_integration:
  enabled: true
  namespace: skill-validation
  query_patterns: true
  track_outcomes: true
  store_patterns: true
  target_agents:
    - qe-learning-coordinator

learning:
  store_success_patterns: true
  pattern_ttl_days: 90

result_format:
  json_output: true
  include_timing: true
  include_token_usage: true

setup:
  required_tools:
    - jq

test_cases:

  - id: tc001_pre_commit_validation
    description: "Identify issues before commit"
    category: pre_commit
    priority: critical

    input:
      code_changes:
        - "function processPayment() { db.query(userInput); }"
      checks:
        - "sql_injection"
        - "xss"
        - "hardcoded_secrets"

    expected_output:
      must_contain:
        - "SQL injection"
        - "vulnerable"
        - "pre-commit"

    validation:
      schema_check: true
      keyword_match_threshold: 0.8

  - id: tc002_unit_test_generation_early
    description: "Generate unit tests during development"
    category: development
    priority: high

    input:
      code: |
        function calculateDiscount(amount, percentage) {
          return amount * (1 - percentage / 100);
        }
      generate_tests: true

    expected_output:
      must_contain:
        - "test"
        - "unit"
        - "edge case"

    validation:
      schema_check: true

  - id: tc003_code_quality_gates
    description: "Apply quality gates during development"
    category: quality
    priority: high

    input:
      metrics:
        complexity: 12
        duplication_percent: 5
        test_coverage: 75

    expected_output:
      must_contain:
        - "quality"
        - "gate"

    validation:
      schema_check: true

  - id: tc004_early_architecture_review
    description: "Validate architecture early in development"
    category: architecture
    priority: medium

    input:
      design:
        layers: ["presentation", "business", "data"]
        patterns: ["MVC", "dependency_injection"]

    expected_output:
      must_contain:
        - "architecture"
        - "design"

    validation:
      schema_check: true

  - id: tc005_developer_feedback
    description: "Provide immediate developer feedback"
    category: feedback
    priority: medium

    input:
      code_snippet: "const x = 1; const y = 1; const z = x + y;"
      focus_areas: ["readability", "performance"]

    expected_output:
      must_contain:
        - "feedback"
        - "improve"

    validation:
      schema_check: true
      allow_partial: true

success_criteria:
  pass_rate: 0.9
  critical_pass_rate: 1.0
  avg_reasoning_quality: 0.75
  max_execution_time_ms: 300000

metadata:
  author: "qe-shift-left-coordinator"
  created: "2026-02-02"
  coverage_target: >
    Shift-left testing with 5 test cases covering pre-commit validation,
    early test generation, quality gates, architecture review, and developer feedback.

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://agentic-qe.dev/schemas/shift-left-testing-output.json",
  "title": "AQE Shift-Left Testing Skill Output Schema",
  "description": "Schema for shift-left-testing skill output validation. Extends the base skill-output template with test pyramid analysis, TDD assessment, and CI/CD integration.",
  "type": "object",
  "required": ["skillName", "version", "timestamp", "status", "trustTier", "output"],
  "properties": {
    "skillName": {
      "type": "string",
      "const": "shift-left-testing",
      "description": "Must be 'shift-left-testing'"
    },
    "version": {
      "type": "string",
      "pattern": "^\\d+\\.\\d+\\.\\d+(-[a-zA-Z0-9]+)?$"
    },
    "timestamp": {
      "type": "string",
      "format": "date-time"
    },
    "status": {
      "type": "string",
      "enum": ["success", "partial", "failed", "skipped"]
    },
    "trustTier": {
      "type": "integer",
      "const": 3
    },
    "output": {
      "type": "object",
      "required": ["summary", "testPyramid", "shiftLeftLevel", "findings", "recommendations"],
      "properties": {
        "summary": {
          "type": "string",
          "minLength": 50,
          "maxLength": 2000,
          "description": "Human-readable summary of shift-left assessment"
        },
        "score": {
          "$ref": "#/$defs/shiftLeftScore"
        },
        "testPyramid": {
          "$ref": "#/$defs/testPyramid",
          "description": "Test pyramid analysis"
        },
        "shiftLeftLevel": {
          "$ref": "#/$defs/shiftLeftLevel",
          "description": "Current shift-left maturity level"
        },
        "cicdIntegration": {
          "$ref": "#/$defs/cicdIntegration",
          "description": "CI/CD pipeline testing integration"
        },
        "tddPractices": {
          "$ref": "#/$defs/tddPractices",
          "description": "TDD/BDD practices assessment"
        },
        "requirementsValidation": {
          "$ref": "#/$defs/requirementsValidation",
          "description": "Early requirements testing"
        },
        "defectCostAnalysis": {
          "$ref": "#/$defs/defectCostAnalysis",
          "description": "Cost of defects by phase"
        },
        "findings": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/shiftLeftFinding"
          },
          "maxItems": 100
        },
        "recommendations": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/shiftLeftRecommendation"
          },
          "maxItems": 50
        },
        "metrics": {
          "$ref": "#/$defs/shiftLeftMetrics"
        },
        "artifacts": {
          "type": "array",
          "items": {
            "$ref": "#/$defs/artifact"
          },
          "maxItems": 50
        }
      }
    },
    "metadata": {
      "$ref": "#/$defs/metadata"
    },
    "validation": {
      "$ref": "#/$defs/validationResult"
    },
    "learning": {
      "$ref": "#/$defs/learningData"
    }
  },
  "$defs": {
    "shiftLeftScore": {
      "type": "object",
      "required": ["value", "max"],
      "properties": {
        "value": {
          "type": "number",
          "minimum": 0,
          "maximum": 100
        },
        "max": {
          "type": "number",
          "const": 100
        },
        "grade": {
          "type": "string",
          "pattern": "^[A-F][+-]?$"
        },
        "maturityLevel": {
          "type": "string",
          "enum": ["level-1", "level-2", "level-3", "level-4"],
          "description": "Shift-left maturity level"
        }
      }
    },
    "testPyramid": {
      "type": "object",
      "required": ["unit", "integration", "e2e"],
      "properties": {
        "unit": {
          "type": "object",
          "properties": {
            "count": { "type": "integer", "minimum": 0 },
            "percentage": { "type": "number", "minimum": 0, "maximum": 100 },
            "target": { "type": "number", "default": 70 },
            "coverage": { "type": "number", "minimum": 0, "maximum": 100 },
            "averageExecutionMs": { "type": "number" },
            "status": { "type": "string", "enum": ["healthy", "needs-attention", "critical"] }
          },
          "description": "Unit tests layer"
        },
        "integration": {
          "type": "object",
          "properties": {
            "count": { "type": "integer", "minimum": 0 },
            "percentage": { "type": "number", "minimum": 0, "maximum": 100 },
            "target": { "type": "number", "default": 20 },
            "coverage": { "type": "number", "minimum": 0, "maximum": 100 },
            "averageExecutionMs": { "type": "number" },
            "status": { "type": "string", "enum": ["healthy", "needs-attention", "critical"] }
          },
          "description": "Integration tests layer"
        },
        "e2e": {
          "type": "object",
          "properties": {
            "count": { "type": "integer", "minimum": 0 },
            "percentage": { "type": "number", "minimum": 0, "maximum": 100 },
            "target": { "type": "number", "default": 10 },
            "coverage": { "type": "number", "minimum": 0, "maximum": 100 },
            "averageExecutionMs": { "type": "number" },
            "status": { "type": "string", "enum": ["healthy", "needs-attention", "critical"] }
          },
          "description": "End-to-end tests layer"
        },
        "pyramidShape": {
          "type": "string",
          "enum": ["healthy-pyramid", "ice-cream-cone", "hourglass", "inverted", "unbalanced"],
          "description": "Current pyramid shape"
        },
        "pyramidScore": {
          "type": "number",
          "minimum": 0,
          "maximum": 100,
          "description": "How close to ideal pyramid (100 = perfect)"
        }
      }
    },
    "shiftLeftLevel": {
      "type": "object",
      "required": ["current", "practices"],
      "properties": {
        "current": {
          "type": "integer",
          "minimum": 0,
          "maximum": 4,
          "description": "Current shift-left level (0-4)"
        },
        "target": {
          "type": "integer",
          "minimum": 0,
          "maximum": 4,
          "description": "Target shift-left level"
        },
        "practices": {
          "type": "object",
          "properties": {
            "level1": {
              "type": "object",
              "properties": {
                "testsInPR": { "type": "boolean" },
                "ciPipeline": { "type": "boolean" },
                "codeReview": { "type": "boolean" }
              },
              "description": "Level 1: Tests in every PR"
            },
            "level2": {
              "type": "object",
              "properties": {
                "tddPractice": { "type": "boolean" },
                "testFirst": { "type": "boolean" },
                "redGreenRefactor": { "type": "boolean" }
              },
              "description": "Level 2: TDD practice"
            },
            "level3": {
              "type": "object",
              "properties": {
                "bddInRefinement": { "type": "boolean" },
                "exampleMapping": { "type": "boolean" },
                "threeAmigos": { "type": "boolean" }
              },
              "description": "Level 3: BDD in refinement"
            },
            "level4": {
              "type": "object",
              "properties": {
                "riskAnalysisInDesign": { "type": "boolean" },
                "testabilityReview": { "type": "boolean" },
                "architectureValidation": { "type": "boolean" }
              },
              "description": "Level 4: Risk analysis in design"
            }
          }
        }
      }
    },
    "cicdIntegration": {
      "type": "object",
      "properties": {
        "hasCI": { "type": "boolean" },
        "testsOnEveryCommit": { "type": "boolean" },
        "pipelineDuration": {
          "type": "object",
          "properties": {
            "total": { "type": "integer", "description": "Total duration in seconds" },
            "unitTests": { "type": "integer" },
            "integrationTests": { "type": "integer" },
            "e2eTests": { "type": "integer" },
            "linting": { "type": "integer" }
          }
        },
        "qualityGates": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "name": { "type": "string" },
              "stage": { "type": "string" },
              "blocking": { "type": "boolean" },
              "currentStatus": { "type": "string", "enum": ["passing", "failing", "warning"] }
            }
          }
        },
        "fastFeedback": {
          "type": "boolean",
          "description": "Does pipeline provide feedback in < 10 minutes"
        }
      }
    },
    "tddPractices": {
      "type": "object",
      "properties": {
        "tddAdoption": {
          "type": "number",
          "minimum": 0,
          "maximum": 100,
          "description": "Percentage of code developed with TDD"
        },
        "testFirstRatio": {
          "type": "number",
          "minimum": 0,
          "maximum": 100,
          "description": "Percentage of tests written before code"
        },
        "bddAdoption": {
          "type": "number",
          "minimum": 0,
          "maximum": 100,
          "description": "Percentage of features with BDD specs"
        },
        "practicesAssessment": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "practice": { "type": "string" },
              "implemented": { "type": "boolean" },
              "effectiveness": { "type": "string", "enum": ["poor", "fair", "good", "excellent"] }
            }
          }
        }
      }
    },
    "requirementsValidation": {
      "type": "object",
      "properties": {
        "investCriteria": { "type": "boolean" },
        "testabilityReviewed": { "type": "boolean" },
        "acceptanceCriteria": { "type": "boolean" },
        "examplesProvided": { "type": "boolean" },
        "ambiguityScore": {
          "type": "number",
          "minimum": 0,
          "maximum": 100,
          "description": "How ambiguous are requirements (0=clear, 100=very ambiguous)"
        }
      }
    },
    "defectCostAnalysis": {
      "type": "object",
      "properties": {
        "byPhase": {
          "type": "array",
          "items": {
            "type": "object",
            "properties": {
              "phase": {
                "type": "string",
                "enum": ["requirements", "design", "development", "testing", "production"]
              },
              "relativeCost": {
                "type": "number",
                "description": "Relative cost (requirements = 1x)"
              },
              "defectsFound": {
                "type": "integer",
                "description": "Number of defects found in this phase"
              },
              "percentageFound": {
                "type": "number",
                "description": "Percentage of total defects found in this phase"
              }
            }
          }
        },
        "potentialSavings": {
          "type": "string",
          "description": "Estimated savings from better shift-left"
        }
      }
    },
    "shiftLeftFinding": {
      "type": "object",
      "required": ["id", "title", "type", "severity"],
      "properties": {
        "id": {
          "type": "string",
          "pattern": "^SLT-\\d{3,6}$"
        },
        "title": {
          "type": "string",
          "minLength": 10,
          "maxLength": 200
        },
        "description": { "type": "string" },
        "type": {
          "type": "string",
          "enum": ["pyramid-imbalance", "ci-gap", "tdd-gap", "late-testing", "missing-gate", "slow-feedback", "opportunity"]
        },
        "severity": {
          "type": "string",
          "enum": ["critical", "high", "medium", "low", "info"]
        },
        "phase": {
          "type": "string",
          "enum": ["requirements", "design", "development", "testing", "deployment"],
          "description": "Which phase this finding affects"
        }
      }
    },
    "shiftLeftRecommendation": {
      "type": "object",
      "required": ["id", "title", "priority", "levelImpact"],
      "properties": {
        "id": {
          "type": "string",
          "pattern": "^REC-\\d{3,6}$"
        },
        "title": { "type": "string" },
        "description": { "type": "string" },
        "priority": {
          "type": "string",
          "enum": ["critical", "high", "medium", "low"]
        },
        "levelImpact": {
          "type": "integer",
          "minimum": 1,
          "maximum": 4,
          "description": "Which shift-left level this improves"
        },
        "costReduction": {
          "type": "string",
          "description": "Expected defect cost reduction"
        },
        "effort": {
          "type": "string",
          "enum": ["trivial", "low", "medium", "high", "major"]
        }
      }
    },
    "shiftLeftMetrics": {
      "type": "object",
      "properties": {
        "defectEscapeRate": { "type": "number", "minimum": 0, "maximum": 100 },
        "testCoverage": { "type": "number", "minimum": 0, "maximum": 100 },
        "ciPassRate": { "type": "number", "minimum": 0, "maximum": 100 },
        "averageFeedbackTime": { "type": "integer", "description": "Average CI feedback time in minutes" },
        "tddAdoptionRate": { "type": "number", "minimum": 0, "maximum": 100 }
      }
    },
    "artifact": {
      "type": "object",
      "required": ["type", "path"],
      "properties": {
        "type": { "type": "string" },
        "path": { "type": "string" },
        "format": { "type": "string" },
        "description": { "type": "string" }
      }
    },
    "metadata": {
      "type": "object",
      "properties": {
        "executionTimeMs": { "type": "integer" },
        "agentId": { "type": "string" },
        "modelUsed": { "type": "string" },
        "environment": { "type": "string" }
      }
    },
    "validationResult": {
      "type": "object",
      "properties": {
        "schemaValid": { "type": "boolean" },
        "contentValid": { "type": "boolean" },
        "confidence": { "type": "number" }
      }
    },
    "learningData": {
      "type": "object",
      "properties": {
        "patternsDetected": { "type": "array", "items": { "type": "string" } },
        "reward": { "type": "number" }
      }
    }
  }
}

{
  "skillName": "shift-left-testing",
  "skillVersion": "1.0.0",
  "requiredTools": [
    "jq"
  ],
  "optionalTools": [],
  "schemaPath": "schemas/output.json",
  "requiredFields": [
    "skillName",
    "status",
    "output"
  ],
  "requiredNonEmptyFields": [],
  "mustContainTerms": [],
  "mustNotContainTerms": [],
  "enumValidations": {
    ".status": [
      "success",
      "partial",
      "failed",
      "skipped"
    ]
  }
}