# Configuration
> The environment variables and resolution rules that configure CGraph.
[Source](https://open.nxtsoft.io/docs/cgraph/configuration)

CGraph is configured mostly through flags (see the
[CLI Reference](/docs/cgraph/cli)) and a small set of environment variables. This
page collects the environment and the resolution rules that decide what runs
against what.

## Environment variables

| Variable | Used by | Meaning |
| --- | --- | --- |
| `VCPKG_ROOT` | build | Path to vcpkg for the CMake build. |
| `CLAUDE_PROJECT_DIR` | `cgraph-mcp` | Project root when no `--root` is given (set by Claude Code). |
| `CGRAPH_DAEMON_PATH` | `cgraph-mcp` | Explicit path to the `graphd` binary. |

## Root resolution

When `cgraph-mcp` needs the project root, it resolves in priority order:

```text
--root flag  >  CLAUDE_PROJECT_DIR  >  working directory
```

## Daemon discovery

When `cgraph-mcp` needs the daemon, it resolves in priority order:

```text
--daemon <path>  >  CGRAPH_DAEMON_PATH  >  graphd next to the binary  >  build-tree layout
```

This layered resolution is why an agent usually needs no configuration: with the
binaries built side by side and `CLAUDE_PROJECT_DIR` set, the defaults resolve
correctly.

## Output location

The graph and its exports are written to the directory given by `--out`
(conventionally `cgraph-out/`), which is also where the daemon re-persists
incremental state.

CGraph does not have a documented configuration *file* in the public README —
behavior is driven by flags, the enrichment drop directory, and the environment
variables above. If a config-file format exists in the source, it is intentionally
not documented here until it can be verified. This section will be expanded from
the real configuration surface, not invented.