> ## Documentation Index
> Fetch the complete documentation index at: https://theagenticguy.github.io/opencodehub/llms.txt
> Use this file to discover all available pages before exploring further.
> Scoped bundles: [user-guide](https://theagenticguy.github.io/opencodehub/_llms-txt/user-guide.txt) · [mcp](https://theagenticguy.github.io/opencodehub/_llms-txt/mcp.txt) · [contributing](https://theagenticguy.github.io/opencodehub/_llms-txt/contributing.txt)

# What is OpenCodeHub?

AI coding agents have a structural blind spot. They can read a file, but
they can't see the graph the file lives in. That blind spot produces
three failure modes every agent-driven workflow eventually hits:

- **Missed dependencies.** The agent renames a function and leaves
  callers untouched, because `grep` found a fraction of the call sites.
- **Broken call chains.** The agent changes a return shape, a handler
  two hops downstream crashes at runtime, and neither the agent nor its
  tests flag it. The relationship was never in context.
- **Blind edits.** The agent rewrites a critical-path function without
  knowing it sits on the hot path of multiple production flows, because
  nothing computed that ahead of time.

Grep is textual. Language servers are per-file. Embeddings are lossy.
None of them answer the questions an agent needs answered *before* it
writes a diff: what breaks if I change this, what depends on this, and
where does this data flow.

## The graph-first approach

OpenCodeHub parses your repository with tree-sitter (15 GA languages,
plus SCIP indexers for TypeScript, Python, Go, Rust, and Java),
resolves imports and inheritance, and materialises a **typed symbol
graph**. That graph is stored in LadybugDB, a graph-native database,
with DuckDB carrying the temporal sibling (cochanges and the
symbol-summary cache). DuckDB also serves as a single-file fallback
for environments where the `@ladybugdb/core` binding cannot load.
BM25 lexical search and filter-aware HNSW vector search sit on the
same store. A local MCP server exposes the graph to any agent that
speaks Model Context Protocol.

```mermaid
flowchart LR
  A[Source tree] -->|tree-sitter parse| B[Symbol graph]
  B -->|resolve imports and MRO| C[Typed relations]
  C -->|BM25 plus HNSW index| D[Hybrid graph store]
  C -->|detect communities and flows| E[Processes and clusters]
  D --> F[MCP server]
  E --> F
  F -->|29 tools| G[AI coding agent]
```

Clustering, execution-flow tracing, and blast-radius analysis all happen
once at index time. Agents get complete relational context in one tool
call, not ten round-trips.

## What you get in v1

- **Graph-native storage by default.** LadybugDB is the default backend;
  a dedicated DuckDB sibling serves the temporal store. A single-file
  DuckDB layout is the opt-in fallback via `CODEHUB_STORE=duck`.
- **Cross-repo federation.** Group several indexed repos with `codehub
  group` and query them through the `group_*` MCP tools. The repo is a
  first-class graph node and `repo_uri` carries through every
  cross-repo response, including the `AMBIGUOUS_REPO` envelope.
- **Deterministic code-pack.** `pack_codebase` (MCP) and `codehub
  code-pack` produce a reproducible 9-item BOM signed by the release
  workflow.
- **WASM-default parsing.** `web-tree-sitter` is the default runtime on
  Node 22 and Node 24; opt into the native N-API addon with
  `OCH_NATIVE_PARSER=1` on Node 22 dev boxes.

## When to reach for OpenCodeHub

- **Non-trivial refactors.** Rename a function, change a return shape,
  or move a module and let the agent see every caller before it edits.
- **Cross-file changes.** Any diff that touches more than one file and
  crosses a module boundary.
- **Blast-radius questions.** "What processes depend on `validateUser`?
  What is the risk tier of this change?"
- **Onboarding to a new repo.** Ask the graph for the top clusters,
  HTTP routes, or authentication flow before the first edit.

Next, [install the CLI](/opencodehub/start-here/install/) and run your
[first query](/opencodehub/start-here/first-query/).

## See also

* [Install](/opencodehub/start-here/install/)
* [Quick start](/opencodehub/start-here/quick-start/)
* [MCP overview](/opencodehub/mcp/overview/)