Testing and documentation

Tests and docs ship with the code

Coverage and living docs are first-class outputs.

01Describe
02Plan
03Build
04Deploy

Tests and docs evidence

Receipts
Checks
  • Unit suite
  • Integration
  • Deploy health
Cited files
  • app/api/checkout.ts
  • lib/billing/invoice.py
  • tests/checkout.spec.ts
Blast radius

3 services · 11 files · 0 shared schemas

Checks green. Staging URL live. Spend recorded on the same thread.

The category

Generation without checks is a liability. Arvad attaches suites and docs to the project so the shareable link includes green checks, cited files, and docs that moved with the change.

  • Suites run on the same project as the build

  • Share view shows suite status and cited files

  • Living docs sync when code changes on the project

  • Failed checks block a shareable green status

The gap

AI coding tools ship fast and break faster

Most AI coding tools optimize for generation, not quality. You get more code, more bugs, more security issues, and docs that never appear. The 2024–2025 data is clear.

10×

More Security Issues With AI

Apiiro's September 2025 study of Fortune 50 enterprises found AI-assisted developers generate 10× more security issues than non-AI peers, including a 322% increase in privilege escalation paths and 153% increase in architectural design flaws.

Apiiro, September 2025

24.8%

Of AI-Generated Tests Actually Execute

An FSE 2024 study found only 24.8% of AI-generated unit tests pass execution. 57.9% fail to compile entirely, and of those that do compile, 85.5% of failures are caused by incorrect assertions, the tests are wrong, not the code.

FSE 2024 / arXiv

59%

Use AI Code They Don't Understand

Clutch's 2025 survey of 800 software professionals found 59% of developers use AI-generated code they do not fully understand. Sonar reports 96% don't fully trust AI output, yet only 48% verify it before committing.

Clutch & Sonar, 2025

Increase in Duplicated Code

GitClear's 2025 analysis of 211 million changed lines found code duplication increased 8× during 2024. Code refactoring dropped from 25% to under 10% of changes. For the first time, copy/paste exceeded refactoring.

GitClear, 2025

AI test generation fails the benchmarks that matter

Independent benchmarks show assistants often fail at tests that catch bugs.

5-29%

Copilot Test Coverage

Diffblue's 2025 benchmark found GitHub Copilot achieves only 5-29% code coverage when generating tests. Claude Code managed 7-17%. 12% of Copilot's generated tests fail to compile entirely.

Diffblue Benchmark, 2025

4%

Mutations Caught Despite 100% Coverage

The MutGen study showed LLMs can generate tests with 100% line coverage that catch only 4% of mutations, tests that execute every line but miss 96% of potential bugs. Coverage is a vanity metric.

MutGen / arXiv, 2025

45%

AI Code Has OWASP Top 10 Vulnerabilities

Veracode's July 2025 report across 100+ LLMs and 80 coding tasks found 45% of AI-generated code introduces OWASP Top 10 security vulnerabilities. Java showed a 72% security failure rate.

Veracode, July 2025

2,500%

Predicted Defect Increase

Gartner predicts prompt-to-app approaches will increase software defects by 2,500% by 2028, driven by "context-deficient code" that lacks system architecture awareness.

Gartner Predicts, Dec 2025

Most AI tools treat testing as an afterthought

Quality is rarely a first-class output beside the generated code.

GitHub Copilot

20M+ users · Market leader
5-29%
Test coverage
12%
Tests fail to compile
60%
Mutation score
Manual
Test generation trigger
University of Turku research found Copilot test generation "inconsistent and frequently requires human intervention" with common test smells including Magic Number Tests and Lazy Tests.
View full case study

Cursor

$29.3B valuation · IDE-first
None
Test validation
None
Coverage tracking
None
Mutation testing
Manual
Documentation
Cursor only generates code, it does not validate whether tests run, fail, or are high quality. Requires constant developer oversight for any testing workflow.
EarlyAI, Comparative Analysis
View full case study

Devin (Cognition AI)

Autonomous AI agent
67%
PR merge rate
33%
PRs rejected
Junior
Execution quality
Manual
Test review needed
Cognition's own November 2025 review described Devin as "senior-level at codebase understanding but junior at execution." They acknowledge humans must check test logic after Devin takes the first pass.
Cognition AI, Annual Performance Review
View full case study

Amazon Q Developer

AWS ecosystem
1 file
At-a-time testing
Java/Python
Languages only
None
Integration tests
None
Auto-documentation
Amazon Q launched unit test generation in December 2024, but operates on a single file at a time with no cross-file architectural awareness or integration test capability.
View full case study

Qodo (CodiumAI)

Test-focused → pivoted to code review
Pivoted
Away from testing
Archived
Open-source tool
Review
Primary focus now
Gartner
Visionary quadrant
Started as a test generation tool but pivoted primary focus to code review. Their open-source test generation tool (Qodo Cover) is no longer actively maintained.
View full case study

The Gap Every Tool Shares

What Arvad AI solves
0
Generate tests with code
0
Auto-document intent
0
Enforce quality gates
0
Continuous test sync
No current AI coding tool generates production-quality tests and documentation alongside code as first-class outputs. Testing is always manual, always secondary, always an afterthought.

Code-only AI vs tests and docs with the build

Current tools generate code. Arvad keeps tests, docs, and deploy in the same workspace as the change.

CapabilityCode-only AI toolsArvad
Test GenerationManual prompt required, 5-29% coverageAutomatic with every build
Test Quality24.8% execution rate, 4% mutation catchValidated tests with mutation-aware generation
Integration TestsNot supported (single-file only)Cross-service API and database tests included
E2E Test SuitesNot generatedCritical user flows tested automatically
DocumentationNot generated or quickly outdatedDocs stay attached and update with the change
Architecture DocsManual or nonexistentGenerated from codebase analysis, kept current
API DocumentationSeparate tool (Swagger/OpenAPI)Auto-generated specs, examples, and guides
Code Intent / "Why"Never documented by AIBusiness logic and design decisions captured
Security Testing45% OWASP vulnerabilities introducedSecurity patterns enforced, OWASP scans built-in
Quality GatesManual CI/CD setup requiredBuilt-in coverage thresholds, mutation scores

Tests and docs built into every build

Treat testing and documentation as first-class outputs, automated with each build.

Unit Test Generation

Unit tests aimed at real defects, not vanity coverage.

Stays in the workspace with plan and checks

Integration & API Testing

Cross-service, database, and API contract tests with the build.

Stays in the workspace with plan and checks

E2E Test Suites

E2E suites for critical user flows before deploy.

Stays in the workspace with plan and checks

Security Test Generation

Security scans in the generation path.

Stays in the workspace with plan and checks

Living API Documentation

OpenAPI specs and examples generated from code and updated with changes.

Stays in the workspace with plan and checks

Architecture & Intent Docs

Docs cover what the code does and why the design chose it.

Stays in the workspace with plan and checks

Continuous Sync

Tests and docs update as code changes.

Stays in the workspace with plan and checks

Quality Gates & Metrics

Coverage thresholds, mutation scores, and scan results gate the shareable green status.

Stays in the workspace with plan and checks

From build to production-ready software

Quality practices run with every build cycle, not as a later cleanup.

The Cost of Shipping Without Tests

Bugs found in production cost far more than bugs caught in development. Third-party research below.

$2.41T

Annual Cost of Poor Software Quality

CISQ estimated the cost of poor software quality in the U.S. reached $2.41 trillion in 2022, with accumulated technical debt at $1.52 trillion. AI-generated code without tests is accelerating this crisis.

CISQ / Synopsys, 2022

42%

Developer Time on Maintenance

Stripe's Developer Coefficient found developers spend 42% of their work week (17.3 hours) on maintenance, debugging, and refactoring, representing $85 billion in annual opportunity cost globally.

Stripe Developer Coefficient, 2018

40-90%

Fewer Defects With Test-Driven Development

Microsoft Research and IBM's landmark study found TDD reduces pre-release defect density by 40-90% across industrial teams, at a cost of only 15-35% more initial development time.

Nagappan et al., Microsoft Research

100×

Cost Multiplier for Production Bugs

The IBM Systems Sciences Institute finding: fixing a bug costs 1× during requirements, 6× during implementation, and up to 100× in production. AI-generated code without tests skips straight to production risk.

Elite teams ship with continuous testing

DORA research across large samples ties automated testing and docs to performance.

3.7×

More Likely to Use Continuous Testing

DORA found elite teams are 3.7× more likely to leverage continuous testing and 5.8× more likely to leverage continuous integration. Manual testing accounts for only 10% of their effort.

DORA / Google, Multi-year

2.4×

More Likely to Meet Reliability Targets

Teams with quality documentation are 2.4× more likely to meet reliability targets and 3.8× more likely to implement security practices. Documentation isn't nice-to-have, it's a performance multiplier.

DORA Report, 2024

50%

Faster Developer Onboarding

Organizations with comprehensive documentation report 50%+ reduction in developer onboarding time and 75% less senior-developer time needed for support. Google identified poor docs as a top-3 onboarding hindrance.

DX Research / Google

78-93%

Cost Reduction From Test Automation

Organizations implementing comprehensive automated testing report 78-93% reduction in quality-related expenses, 40-75% faster release velocity, and 50-80% fewer production defects.

Industry Analysis

The gap

Vibe coding makes quality automation urgent

Vibe coding (Collins Dictionary Word of the Year 2025) means accepting AI output without understanding or testing it. That habit is moving into enterprise workflows.

36%

Vibe Coders Skip QA Entirely

A 2025 arXiv grey literature review found 36% of vibe coders accept AI output without any validation. Only 29% perform manual testing. The speed-first mindset is creating untested, undocumented production code at scale.

arXiv Grey Literature Review, 2025

69

Vulnerabilities Across 5 AI Tools

Tenzai tested Claude Code, OpenAI Codex, Cursor, Replit, and Devin across 15 applications and found 69 total vulnerabilities, with approximately half a dozen rated "critical." A Wiz study found 20% have serious security issues.

Tenzai Assessment, Dec 2025

45%

Say Debugging AI Code Takes More Time

Stack Overflow 2025: 45% of developers say debugging AI-generated code is more time-consuming than debugging their own. Trust in AI accuracy fell to just 29%. Positive sentiment dropped from 70%+ to 60%.

Stack Overflow Developer Survey, 2025

19%

Experienced Devs Slower With AI

The METR RCT found experienced developers using AI were 19% slower yet believed they were 20% faster. The perception gap is dangerous, teams think they're shipping quality when they're shipping debt.

METR Randomized Controlled Trial, 2025

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Research behind quality-first AI development

Stats on this page cite published research. Read the sources.

AI Test Generation Benchmarks

Straight answers

Limits stated plainly. No demo theater.

One question

When the build finishes, can you show a teammate the plan, preview, tests, and deploy status without digging through chat?

If you cannot, you still have a chat log. Arvad keeps that work in one workspace.

Ship with checks on the build

Tests and docs ship with the change, not as an afterthought.