subagentidentities

cargo run -p agent-gen requires RUSTC_WRAPPER='' on this machine to bypass a broken sccache wrapper — without it, rustc invocation fails with "could not execute process sccache ... (never executed)".

A machine-local toolchain quirk, not a portable rule — narrower than the repo-wide sandbox rule, and only adds an override on top of it, never replaces it (the same "narrower scope adds, doesn't replace" rule attach-to-scope.md states for overlapping Access bundles).

custom instructions

CLAUDE.md, "Type-safe agent system", "crates/agent-gen/"