Using Git Notes For AI Context

Using Git Notes for AI Context

Git notes and trailers form a zero-infrastructure metadata layer for AI agent context. Notes attach post-hoc metadata without changing commit SHAs. Trailers embed structured key-value pairs inside commit messages.

Notes vs. trailers

Rule of thumb: If the metadata should travel with the commit and be visible in git log, use trailers. If the metadata is post-hoc, verbose, or machine-generated, use notes.

When authoring commits, keep subject/body format aligned with the repository's commit convention; this skill focuses on metadata structure, storage, and querying.

Workflows

Identify the task, then follow the matching workflow.

Annotating commits with AI context

1. Decide notes vs. trailers using the table above.
2. For notes — select the namespace per references/01-core-concepts-and-namespaces.md §Namespace Scheme:

   git notes --ref=ai/attribution add -m \
     '{"schema":"ai-context/1.0","agent":{"tool":"claude-code","model":"claude-opus-4-6"}}' HEAD
   

3. For trailers — include footer lines in the commit message during commit creation (using your team's normal commit flow), for example:

   AI-Agent: claude-code/claude-opus-4-6
   Constraint: Must remain backward-compatible
   

4. Verify: git notes --ref=ai/attribution show HEAD or git log -1 --format='%(trailers)' HEAD.
5. To automate, install hooks — see references/03-hooks-scripts-and-automation.md.

Querying context before modifying code

1. Harvest existing constraints, directives, and rejected approaches:

   git log --format='%(trailers:key=Constraint,key=Directive,key=Rejected)' -- <file>
   

2. Check AI attribution notes:

   for sha in $(git log --format='%H' -- <file>); do
       git notes --ref=ai/attribution show "$sha" 2>/dev/null
   done
   

3. Use this context to avoid repeating rejected approaches and honor active constraints and directives.

Setting up git notes infrastructure

1. Configure remote sync:

   git config --add remote.origin.fetch '+refs/notes/*:refs/notes/*'
   git config --add remote.origin.push '+refs/notes/*:refs/notes/*'
   

2. Configure rebase survival:

   git config --add notes.rewriteRef "refs/notes/ai/attribution"
   git config notes.rewrite.rebase true
   git config notes.rewrite.amend true
   

3. Verify sync works:

   git push origin 'refs/notes/*' --dry-run
   

4. Install hooks for automatic annotation — see references/03-hooks-scripts-and-automation.md.
5. For teams: add onboarding script and namespace governance — see references/04-team-enterprise-and-security.md.

Choosing tools

Default recommendations:

• Line-level AI attribution: Git AI (git ai init) — broadest agent support (12+), rebase survival, open standard.
• Decision context in commits: Lore protocol trailers — no tool required, just trailer conventions.
• Both: They complement each other.

For detailed comparison, see references/02-use-cases-and-tools.md §Tool Comparison.

Essential commands

# Notes
git notes --ref=ai/attribution add -m 'data' HEAD      # Add
git notes --ref=ai/attribution append -m 'more' HEAD    # Append
git notes --ref=ai/attribution show HEAD                 # Read
git log --show-notes=ai/attribution                      # Show in log

# Trailers (read/query)
git log -1 --format='%(trailers)' HEAD                   # Read all
git log --format='%(trailers:key=Constraint)' -- file    # Filter by key
git log -1 --format=%B HEAD | git interpret-trailers --parse  # Parse raw message

# Sync
git push origin 'refs/notes/*'                           # Push all notes
git fetch origin 'refs/notes/*:refs/notes/*'             # Fetch all notes

Edge cases

• Namespace conflict: refs/notes/ai (bare) cannot coexist with refs/notes/ai/prompts. Always use sub-paths like ai/attribution.
• Git AI ref conflict: Git AI occupies refs/notes/ai (bare). If using Git AI, use non-ai/ prefixes for custom namespaces (e.g., dev/prompts, dev/decisions) to avoid ref conflicts.
• Rebase orphans notes: Configure notes.rewriteRef (see "Setting up" workflow). Git AI handles this automatically.
• Notes not synced by default: Must configure fetch/push refspecs.
• One note per namespace per object: Use append to add to existing notes, or use separate namespaces.
• No GitHub/GitLab UI display: Notes are CLI-only — invisible in web UIs.
• Merge conflicts under concurrency: Configure merge strategy per namespace — see references/04-team-enterprise-and-security.md §Merge Strategies.

Reference material

• Core concepts and namespaces — notes/trailers mechanics, namespace scheme, structured JSON format
• Use cases and tools — Lore protocol, session metadata, CI/CD, tool comparison
• Hooks, scripts, and automation — post-commit/pre-push hooks, GitHub Actions, aliases, context harvest
• Team, enterprise, and security — remote sync, merge strategies, compliance, redaction, signing, limitations