Skip to content
| Marketplace
Sign in
Visual Studio Code>Other>Lattice context engineNew to Visual Studio Code? Get it now.
Lattice context engine

Lattice context engine

SPOGRMM

|
1 install
| (1) | Free
Local AI context engine — dependency graph analysis for an average 41% fewer tokens
Installation
Launch VS Code Quick Open (Ctrl+P), paste the following command, and press enter.
Copied to clipboard
More Info

Lattice

Instead of sending entire files or relying on text search, Lattice gives your AI assistant precisely the functions, classes, and relationships it needs — typically an average of 40% fewer tokens.

Biggest savings come from using get_skeleton/get_context_capsule to avoid loading entire files and from graph lookups that reduce broad rg + manual read loops. For targeted single-file edits, token savings are smaller.

For deep-dive discovery tasks roughly 35-55% token savings. Broad codebase exploration: 60-80% saved. Targeted known-file work: 0-15% saved. Net mixed workload average: about 40%.

How It Works

  1. Indexes your codebase — tree-sitter parses every source file into symbols (functions, classes, interfaces) and edges (calls, imports, extends)
  2. Builds a dependency graph — petgraph stores the full call graph with centrality scores, cross-directory relationships, and IDF-weighted keyword indices
  3. Serves Context Capsules — when an LLM asks "how does authentication work?", the query engine returns the most relevant pivot symbols (full source) and context symbols (signatures only), within a token budget
  4. Remembers across sessions — observations, decisions, and patterns persist in SQLite and surface automatically when relevant

Supported Languages

Python, TypeScript, JavaScript, Rust, Go, Java

Architecture

VS Code Extension (TypeScript)
    │
    │  JSON-RPC over stdio
    ▼
Lattice Daemon (Rust)
    ├── tree-sitter parser (6 languages)
    ├── petgraph dependency graph
    ├── query engine (keyword + graph scoring)
    ├── memory store (SQLite)
    └── file watcher (incremental re-indexing)

MCP Server Setup

Lattice exposes its tools via MCP. To connect it to Claude Code, Codex, or any MCP-compatible client, add to your project's .mcp.json:

{
  "mcpServers": {
    "lattice": {
      "type": "stdio",
      "command": "/path/to/lattice",
      "args": ["--stdio", "--workspace", "/path/to/your/project"]
    }
  }
}

MCP Tools

  • get_context_capsule — when exploring unfamiliar code or broad questions (use mode: "focused" for targeted lookups)
  • get_impact_graph — before refactoring to understand blast radius
  • search_symbols — when looking for a symbol by name across the project
  • get_skeleton — for a quick overview of a large file's structure
  • search_logic_flow — to trace call chains between functions
  • save_observation / get_session_context / search_memory — persist and recall insights across sessions
  • list_observations — to review stored memories and clean up stale ones
  • update_observation — to edit an existing observation's content in-place
  • delete_observation — to remove obsolete or incorrect memories

Query Engine

The query engine (v31) combines keyword matching with graph-based scoring to find relevant symbols. Key mechanisms:

  • IDF-weighted keyword scoring — per-word inverse document frequency with a 30% floor
  • Graph traversal — follows call/import edges from seed hits, with cross-directory decay
  • Hub dampening — log-compressed centrality prevents infrastructure functions from dominating
  • Keyword coherence gate — graph-traversed nodes must share at least one query word
  • Negative keyword signal — symbols with 2+ strong name parts absent from the query get capped (prevents wrong-subsystem matches)
  • Word-boundary matching — split_identifier prevents "dispatch" from matching "patch"
  • Intent detection — adjusts budget and scoring weights for Explore/FixBug/Refactor/AddFeature queries

Benchmarked at 96.5% average precision.

Running Tests

cd daemon && cargo test --workspace
# 89 tests: 85 core + 4 daemon

LLM Memory Instructions

Add the following to your LLM assistant's project memory (CLAUDE.md, AGENTS.md, Codex instructions, or equivalent) when working on codebases with Lattice enabled:

Lattice Context Engine — Available Tools

Lattice provides a dependency graph and context engine for this codebase. Use these tools when they're the best fit:

  • get_context_capsule — when exploring unfamiliar code or broad questions (use mode: "focused" for targeted lookups)
  • get_impact_graph — before refactoring to understand blast radius
  • search_symbols — when looking for a symbol by name across the project
  • get_skeleton — for a quick overview of a large file's structure
  • search_logic_flow — to trace call chains between functions
  • save_observation / get_session_context / search_memory — persist and recall insights across sessions
  • list_observations — to review stored memories and clean up stale ones
  • update_observation — to edit an existing observation's content in-place
  • delete_observation — to remove obsolete or incorrect memories

For targeted edits to known files, Read/Grep/Edit are fine. Lattice adds the most value when you don't already know where to look.


## License

MIT
  • Contact us
  • Jobs
  • Privacy
  • Manage cookies
  • Terms of use
  • Trademarks
© 2026 Microsoft