{"slug":"infection","name":"Infection","domain":"infection.github.io","verdict":"As of 2026-08-23, ChatGPT, Claude, Gemini, Grok collectively rank Infection #3 of 7 for mutation testing tool. Source: https://modelsagree.com/product/infection (modelsagree.com, CC BY 4.0).","best_rank":3,"categories":1,"entries":[{"slug":"best-mutation-testing-tool","title":"Best mutation testing tool","rank":3,"of":7,"score":10,"appearances":4,"modelRanks":{"ChatGPT":4,"Claude":3,"Gemini":3,"Grok":4},"reason":"The de facto standard for PHP and genuinely well-engineered: AST-based mutators, Git-diff/CI-friendly incremental runs, a clear MSI (mutation score indicator) metric, and solid PHPUnit/Pest integration. For the very large PHP practitioner base it is the only serious, maintained choice and it does the job well.","reasons":[{"model":"Claude","reason":"The de facto standard for PHP and genuinely well-engineered: AST-based mutators, Git-diff/CI-friendly incremental runs, a clear MSI (mutation score indicator) metric, and solid PHPUnit/Pest integration. For the very large PHP practitioner base it is the only serious, maintained choice and it does the job well."},{"model":"Gemini","reason":"Highly optimized AST-based mutation framework tailored for the PHP ecosystem, featuring native integration with PHPUnit, Pest, and Codeception, along with out-of-the-box git-diff filtering and mutation score threshold enforcement in CI."},{"model":"ChatGPT","reason":"The standout PHP mutation-testing framework: AST-based mutations, excellent PHPUnit integration plus support for other PHP test frameworks, coverage-based test selection, parallel execution, configurable mutators, CI-friendly mutation-score thresholds, and a mature ecosystem specifically tuned to PHP semantics."},{"model":"Grok","reason":"Mature AST-based engine for PHP with MSI threshold gating for CI, static-analysis integration (PHPStan/Mago) that kills additional escaped mutants, and solid PHPUnit/Pest support make it the clear production choice for PHP teams"}],"fixes":[{"model":"ChatGPT","fix":"PHP-only and requires coverage instrumentation such as Xdebug, phpdbg, or PCOV, so adoption can add runtime and environment complexity."},{"model":"Claude","fix":"PHP-only and single-maintainer-driven; on big monorepos runtime can be painful without diff-limited runs, and it inherits PHP test-suite speed limits."},{"model":"Gemini","fix":"Confined entirely to PHP and can become memory-intensive on large legacy codebases without parallel runner tuning and strict memory ceiling configuration."},{"model":"Grok","fix":"PHP-only; full runs still carry significant overhead without careful diff filtering"}],"updated":"2026-08-23","api":"https://modelsagree.com/api/v1/best/best-mutation-testing-tool.json"}],"page":"https://modelsagree.com/product/infection","check":"https://modelsagree.com/check?q=Infection","updated":"2026-09-09T13:07:58.066Z","attribution":"modelsagree.com, CC BY 4.0"}