What
Several internal fields used when spawning a subagent, running a background bash task, or setting a scheduled reminder or loop are now run through a sanitizer before use:
descriptionandreasonstrings have control characters and unusual formatting characters stripped, extra whitespace collapsed, and leading/trailing whitespace trimmed- these strings are now truncated to 1024 characters, with an ellipsis added if they were cut off
toolUseIdfields (identifiers used to track a specific tool call) must now match a strict pattern of letters, numbers, and the characters_,.,:,-, up to 128 characters, instead of being accepted as any string
Why
This prevents malformed, oversized, or oddly-formatted text from leaking into internal descriptions and reasons, and closes off invalid tool-use identifiers from being accepted where a stricter format was always intended.