The gateway/API server rebuilds the in-memory TodoStore by replaying
caller-supplied conversation_history. _hydrate_todo_store previously
accepted any role:tool message containing a "todos" array, so a forged
bare tool result could seed arbitrary todo state and re-inflate context
every turn (GHSA-5g4g-6jrg-mw3g).
Restrict hydration to tool results paired with an earlier assistant
todo tool call (matching tool_call_id, function name == todo, no
user/system boundary between). Reuse the existing _get_tool_call_id/
name_static helpers so dict- and object-shaped tool calls both work.
Add a generous MAX_TODO_RESULT_CHARS payload guard to drop absurd
forged results before parsing; item/content caps already exist on main.
Co-authored-by: Hermes Agent <agent@nousresearch.com>