After accomplishing Task 2, see Codex_Response... for details.

.agents/skills/lxmf-update/SKILL.md

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+---
+name: lxmf-update
+description: Check upstream LXMF and RNS implementations for changes affecting the LXMF specification, run local verifier tools, and propose spec updates with citations.
+---
+
+# LXMF update skill
+
+Use this skill when asked to check whether the LXMF specification is current with upstream LXMF or RNS.
+
+## Sources of truth
+
+Prefer, in order:
+
+1. Upstream LXMF source code at a pinned release or commit.
+2. Upstream RNS source code where LXMF behavior depends on Reticulum behavior.
+3. Reproducible local traces and test vectors.
+4. Upstream prose documentation, only when consistent with source behavior.
+
+## Required workflow
+
+1. Determine the currently pinned upstream LXMF and RNS versions from `SOURCES.md`.
+2. Check whether newer upstream releases or commits exist.
+3. Identify changed files relevant to:
+   - message packing
+   - fields and flags
+   - destination handling
+   - identity/signature behavior
+   - encryption behavior
+   - propagation
+   - delivery semantics
+   - storage format if externally observable
+4. Run the verifier tools in `tools/`.
+5. Compare observed behavior against `SPEC.md`.
+6. Produce a report with:
+   - changed upstream files
+   - affected specification sections
+   - proposed edits
+   - test-vector impact
+   - unresolved ambiguities
+7. Do not modify `SPEC.md` unless explicitly asked.