Definition
Plain language
The piece of agent expertise that's about how a tool or environment responds when you act on it.
As stated in the literature
In QUEST's decomposition of expert demonstrations, the part of agent skill captured by environment dynamics — what kinds of outputs commands produce, how errors look, how state evolves — separable from higher-level strategy knowledge.
Why it matters: Separating it from strategy helps explain why agents that 'know what to do' still fail in unfamiliar tools — they lack the environmental reflexes.
For example, knowing that 'ls' on an empty directory prints nothing rather than an error, or that a failed git push produces a specific multiline message, is interaction-prior knowledge.
Heard on the show
“One is what they call an *interaction prior* — how does the terminal respond to my commands, what kinds of outputs do I get, how do errors look.”Episode 084 — Terminal Agents Get Free Supervision From The Tokens We've Been Throwing Away