CASTLE
Choose a HAT. The deterministic examiner does the heavy lifting; the GOBLIN brain adds teacher voice when available.
CASTLE · operating system
HATS · task apps
SKULL · constrained decoding
GOBLIN · small browser LLM
KING · future orchestrator
4
EIKEN Grade-2 Writing
Q4 Summary HAT
Read a passage, write a 45–55 word summary, then get deterministic scoring plus GOBLIN feedback.
Open summary simulator →
5
EIKEN Grade-2 Writing
Q5 Essay HAT
Generate or edit a topic, write an 80–100 word opinion essay, then grade against the EIKEN-style rubric.
Open essay simulator →