Context Engine. Now with Full Commit History

Modern AI coding agents are great at reading the files you give them. They stumble, however, when the answer is buried in months of commit history.

Without that lineage, agents often struggle to parse well-established norms:

Joel, one of the engineers behind the feature, summed it up perfectly:

“Often when the agent is trying to do something, something similar has been done before. We want to learn from that thing that was done before and adapt it to a new situation.”

By piping commit history directly into the context engine, Context Lineage closes this historical gap.

Why it matters:

What is Context Lineage

Context Lineage is an upgrade to the Augment Context Engine that:

The result is a context window that spans not just the current codebase but its evolution.

How it works under the hood

1. Commit harvesting inside the IDE

The Augment extension now scans git history alongside workspace files. New commits are detected in near real time and streamed to the backend.

2. Lightweight summarization with Gemini

Raw diffs can be huge. Instead of embedding thousands of lines, we ask Gemini 2.0 Flash to condense each commit into a few sentences with:

This summary, plus metadata, becomes the search document.

3. Indexing and retrieval

Summaries are chunked and embedded alongside normal file chunks. At query time, the agent can use the retrieval tool to find these historical commits.

If matching commits exist, their summaries and metadata are injected into the agent prompt, providing it with historical insight at a token-level cost similar to that of a small file.

Real world benefits and use cases

Context Lineage is live today. You can prompt for the tool call directly by asking for the commit history via questions and prompt like:

Conclusion

Context Lineage represents a big improvement in how AI agents understand codebases—moving from snapshot-based reasoning to evolution-aware intelligence. By connecting agents to your repository's full story, we're not just improving code quality; we're preserving and amplifying institutional knowledge that would otherwise be lost to time.

Ready to give your agents the full picture? We’re currently rolling this out to users in VS Code. Let us know if you notice a difference.