navigation-hardening-pass

name	navigation-hardening-pass
description	Use for LawnBerry Pi navigation hardening work: feedback audit, waypoint progress validation, stop and fault behavior, obstacle gating, interrupted traversal handling, and targeted regression coverage in navigation and mission flows.
argument-hint	What navigation behavior, failure mode, or contract needs hardening?
user-invocable	true

Navigation Hardening Pass

What this skill does

This skill packages the navigation/runtime credibility workflow from the maintainer handbook into a repeatable implementation sequence.

Best use cases

• waypoint progress advancing too optimistically
• pause, abort, interrupt, or fault paths not stopping cleanly
• obstacle hold or lost-position behavior uncertainty
• mission execution depending on navigation behavior without enough feedback evidence

Procedure

1. Start with a navigation feedback audit.
   • trace where the system assumes movement succeeded
   • identify where encoder, GPS, controller, or other feedback actually confirms motion
   • list state transitions that can advance without enough evidence
2. Harden stop and fault behavior.
   • ensure controller failures, obstacle holds, interrupts, and aborts fail closed
   • verify pause and abort paths route through a clean stop path
3. Tighten regression coverage.
   • prioritize service-level and contract-level tests around interrupted waypoint traversal, lost position, obstacle gating, and command-delivery failures
4. Re-run the focused navigation and mission validation slice.
5. Update maintainer docs if subsystem maturity, behavior, or limitations changed materially.

Working rules

• prefer concrete field-feedback evidence over optimistic state updates
• keep behavior deterministic when control or position confidence drops
• do not broaden scope into unrelated autonomy work during a hardening pass
• if navigation service signatures or public helpers changed, sync docs/code_structure_overview.md

Completion checks

• a defect list or risk list exists before edits begin
• stop and interruption semantics are explicit after the change
• regression coverage matches the specific failure mode addressed
• final notes distinguish hardened behavior from remaining field limitations