Definition
Plain language
A way of rewriting data into a plain block of letters and numbers so it can travel safely through text-only channels.
As stated in the literature
A binary-to-text encoding that represents arbitrary bytes using a 64-character alphabet; used in this corpus to hide metadata tags inside assistant messages that are invisible in a human-facing viewer but readable in the raw payload.
Why it matters: It lets binary data move reliably through channels that only handle text, but it can also conceal tags that look invisible in a normal viewer yet remain readable in the raw payload.
For example, a small image or a hidden metadata tag can be turned into a long string of ordinary-looking letters and numbers so it survives being pasted into a text-only message.
Heard on the show
“Base64-encoded, invisible in the human-facing viewer, but fully visible to the model in the raw payload.”Episode 143 — When a Model Notices You Forged Its Own Words, And Why That Breaks Safety Tests