- applyHookContext now replaces only text blocks, keeping images and
tool results intact (was silently stripping them)
- Use backward loop instead of reverse() + find() for efficiency
- Clarify JSDoc that only `prompt` is applied from hook return value
- Add test for mixed-content user messages
Add optional hook callbacks to AgentConfig for cross-cutting concerns
(guardrails, logging, token budgets) without modifying framework internals.
- beforeRun: receives prompt + agent config, can modify or throw to abort
- afterRun: receives AgentRunResult, can modify or throw to fail
- Works with all three execution modes: run(), prompt(), stream()
- 15 test cases covering modify, throw, async, composition, and history integrity
JackChen