Definition
Plain language
A complete recording of one function call inside a program — what came in, what each line did, and what came out.
As stated in the literature
A frame-level dynamic analysis artifact capturing a single function invocation's arguments, ordered statement executions with memory deltas, callees, and return value, used as input to debugging agents.
Why it matters: Giving a debugging agent a complete record of one function's execution is far more useful than a stack trace and matches how human debuggers actually think.
For example, when a buggy function gets called, a Frame Lifetime Trace shows its inputs, each line executed in order with what changed in memory, every sub-function it called, and what it returned.
Heard on the show
“This is the central abstraction, and it has a name — Frame Lifetime Trace — but the name is less interesting than the idea.”Episode 005 — Why a Debugger Designed for Humans Is the Wrong Tool for an AI Agent