Why these tools exist

Writing code got cheap. Checking that it holds up did not.

An agent steering for a green test suite gets a green test suite. An assertion comparing a value with itself passes exactly as hard as one that proves something, and so does a stub for a method that stopped existing months ago. A suite like that is a signature under a document nobody read.

Outside the tests it goes the same way. An agent that does not know your architecture guesses at it, and a guess that is wrong looks just like one that is right. An agent allowed near your database is allowed everything there, unless somebody drew that line.

Three of them read code and tests directly. Knossos-MCP maps the architecture, Chaos-MCP attacks the suite with mutants to find what it never checked, and Momus-MCP audits what the tests actually assert. All three now cover the same four ecosystems: TypeScript and JavaScript, PHP, Python and Rust. A repository that mixes them gets one answer across the lot, instead of one answer per ecosystem and a gap wherever they meet.

That is what these tools are for. Not producing code faster, but seeing what the code you already have actually does.