The context object passed to tool-execution hooks was substantially reworked with many new fields
The context object handed to tool-execution hooks (code that runs around a tool call) was rebuilt. It no longer includes credentials, isNonInteractiveSession, persistedToolResultFiles, artifactRead, or signal. In their place it now carries a much larger set of fields, including agentId, agentWorktree, taskRegistry, readFileState, getFileHistoryState, applyFileHistoryOp, sessionEnvVars, markPrResolvedThisSession, userTypedShellDispatch, emitToolProgress, shellPermission (bundled with abortController and toolUseId), mainLoopModel, effort, effortLayerOverride, unlayeredPermissions, abortController, remoteCall, and innerCall.
This substantially expands what internal hooks and tool-execution code can see and do around a tool call, covering things like agent identity, file-history tracking, and per-call permissions and effort settings, rather than the narrower context passed before.