Agent eXperience Interface (AXI)

AXI defines ergonomic standards for building CLI tools that autonomous agents interact with through shell execution.

Before you start

Read the TOON specification before building any AXI output.

1. Token-efficient output

Use TOON (Token-Oriented Object Notation) as the output format on stdout. TOON provides ~40% token savings over equivalent JSON while remaining readable by agents. Convert to TOON at the output boundary — keep internal logic on JSON.

tasks[2]{id,title,status,assignee}:
  "1",Fix auth bug,open,alice
  "2",Add pagination,closed,bob