Open-source tooling for NASA cFS–style missions that helps teams catch silent MsgID misconfiguration before flight. cFS apps spread numeric topic IDs across many *_topicids.h headers; when two apps reuse the same topic ID in the same Software Bus channel, computed MsgIDs can collide and messages can be misrouted with no compile-time error. cfs-msgid-guard is a TypeScript GitHub Action and CLI that scans the mission tree, computes MsgIDs, and surfaces collisions (for example via PR annotations and job summaries), published on npm. cfs-msgid-sentinel is a Python GitHub Action and CLI that applies the same four-channel collision model with CLI, JSON, and Markdown-style reporting for CI workflows, published on PyPI.