Whippletree: One Pull, Every Harness

Why it surfaced

Whippletree does something unusually valuable for developer tooling: it names its limits. Its preflight output distinguishes native enforcement, degraded stand-ins, instruction-only behavior, and an unimplemented observer tier—then refuses installation when a hard requirement cannot be met honestly.

A Go tool that declares an agent tool’s lifecycle once, compiles it for four coding harnesses, and reports what each harness can actually enforce.