CachePolicy

Declares that a node's result depends only on its input, so a repeated input may be answered from memory without running the node.

The node must not depend on ThreadState, on the clock, or on an external system: a node that needs part of the state takes that part as input. The key is the node, its input schema version and the encoded input. A hit returns the stored Command and the node does not run, so a cached node should not rely on RunContext.emit or progress. Only a Continue result is stored: a failure or a suspension is not.

The cache belongs to the CompiledGraph instance and is shared by its runs. It is not checkpointed, so another instance, another process or a restart starts empty and recomputes. Entries beyond maxEntries are evicted least-recently-used first. Two tasks with one input running at the same time both run the node.

Every value is validated like RunBudgets: apply and the with* setters throw IllegalArgumentException; CachePolicy.of returns a ValidationError.