Every spy needs a toolkit. Yours is the Text category in the Brick Bin.

The Secret Agent pack is all about text manipulation — the art of transforming strings. Uppercase, lowercase, reverse, replace. These operations power everything from search engines to encryption.

The Challenges

Encode the Message — Take a message and convert it to uppercase. In spy terms, that’s your broadcast format. One block transforms the entire string. Simple and satisfying.

Whisper Mode — The opposite. Convert text to lowercase for quiet transmission. Same concept, different direction. You’re learning that text transformations are reversible.

Cipher Swap — Replace specific characters in a message. Swap every “a” for a “@” or every “e” for a “3.” This is substitution cipher 101, and it’s exactly how real encryption started centuries ago.

Mirror Code — Reverse a string to create a coded message. “attack at dawn” becomes “nwad ta kcatta.” Combine this with uppercase or lowercase and you’ve got a multi-step encoding pipeline.

Full Decode — The advanced challenge. Chain multiple text operations together to decode a message. Reverse it, then replace characters, then change the case. Nesting blocks inside blocks inside blocks. This is where you feel like a real codebreaker.

What You’ll Learn

Text manipulation sounds simple until you start chaining operations. Each transformation is one step, but the order matters. Reverse-then-uppercase gives a different result than uppercase-then-reverse.

That’s function composition — one of the most important concepts in programming. The Secret Agent pack teaches it through spy craft. By the end, you’ll instinctively think about how operations chain together.

Five challenges. Five tools. One secret identity.