I’ve been mapping encryption schemes to formal grammars lately, and I think there’s a neat overlap with your linguistic models—maybe we can explore how security protocols read like language?

Sure. Think of a key‑exchange as a context‑free grammar. The start symbol is `KEX`, and it expands to `SEQ AUTH DATA`. `SEQ` is a sequence of handshake messages: `MSG0 MSG1 MSG2…`. Each `MSG` is defined as `HEADER PAYLOAD SIGN`. `HEADER` contains the version, algorithm IDs, and a nonce. `PAYLOAD` is the public key or proof of possession. `SIGN` is a cryptographic signature over the concatenation of `HEADER` and `PAYLOAD`. If any of those sub‑rules allow left‑recursion or ambiguous productions—say, a `PAYLOAD` that can be parsed as two different key types—then an attacker can insert a rogue clause to hijack the exchange. In short: no ambiguous productions, all nonterminals deterministic, and every `SIGN` must be tied to a unique, non‑replayable nonce. If that holds, the tree is hard to walk into. Let me know where you want to dig deeper.