cross-harness-continuation

Cross-Harness Continuation

Use this skill when a task continues after another agent, especially when the handoff is Claude -> Codex, Codex -> Claude, or a plugin has already received several partial fixes.

Operating contract

The repository is the source of truth for code. The continuation contract is the source of truth for intent that Git cannot express:

<repo>/.claude/continuity/CONTINUITY.json

The canonical shape is in references/CONTINUITY.example.json. It must contain:

• mode: continuation for incremental work, new for greenfield work;
• baseline: branch, commit, and paths that were already dirty at handoff;
• scope.files: the files explicitly claimed for the current slice;
• preserve: accepted design decisions and invariants;
• do_not_redo: approaches already tested or deliberately rejected;
• verification: commands and evidence status;
• scope.enforce and scope.protect_unlisted when the slice must be strict.

Required sequence

1. Read CONTINUITY.json, the newest handoff, AGENTS.md/CLAUDE.md, and the current Git status. Treat the live checkout as authoritative over stale prose.
2. Verify the baseline commit, branch, dirty paths, and the claimed files. Preserve existing changes unless a test or the contract proves they are wrong.
3. Make one focused continuation change. Use Edit for existing files. Do not replace a whole file merely because another implementation is easier to write.
4. Run the smallest relevant test, then the independent verifier for a non-trivial or cross-module change. Record commands and outcomes in the contract or handoff.
5. Update the contract with what was preserved, what changed, what failed, and the single next step. Commit a clean, descriptive checkpoint when the project workflow allows it.

Replan boundary

Replanning is valid when measured evidence shows the current design is wrong, the requirements changed, or an explicit user decision authorizes a redesign. Declare it in the process that launches the agent: