Codegraph partner

OSB and codegraph are complementary, not overlapping. OSB owns the vault (Markdown prose, the Brain layer, preferences, paid-action audit). The codegraph CLI and its MCP server own the code-symbol graph of a repository - callers, callees, impact radius, AST. This skill teaches the agent to detect codegraph in the current scope and to use, recommend, or stay quiet about it, depending on what is actually nearby.

This skill never installs, initializes, or writes data for codegraph itself. Those actions stay in the user's hands or in codegraph's own installer.

Step 1 - detect

Run these checks in order. Stop at the first state that matches.

1. CLI presence: which codegraph (or, in Bun runtimes, Bun.which("codegraph")).
2. Code-project signal in the current working directory: a .git/ directory plus at least one of package.json, pyproject.toml, Cargo.toml, go.mod, tsconfig.json, Gemfile, composer.json, build.gradle, pom.xml.
3. If neither cwd nor the user's named project is a code project, look at the vault's parent directory and inspect the top-level entries (one level only). Many users keep their repos as siblings of the vault. All discovered code projects are candidates, not just the first.
4. Index state: a .codegraph/ directory inside the code project root.
5. Confirmed index: codegraph status -j <project_path> returns {"initialized": true, ...}. The same command on an uninitialized project returns {"initialized": false, ...} rather than failing.

The structured way to ask is o2b doctor. When OSB is installed in the workspace, the doctor report carries a code_graph line that summarises the detection result with node count and file count.

Multi-project workspaces: when more than one code project is discovered, the code_graph line covers EVERY project. Status is threaded per project by passing each project's path to codegraph status, and the line aggregates one entry per project (N code projects: followed by a bullet per project naming its path and index state/health). This per-query project-path threading is feature-detected: if the installed codegraph CLI does not document a positional [path] argument for status, OSB cannot trust per-project queries, so it degrades to reporting the first project only and appends an explicit note: codegraph CLI has no per-query project_path support - reported 1 of N discovered projects only. A single-project workspace is unaffected and its line is unchanged.

Step 2 - branch on result

In a multi-project workspace the aggregate code_graph line can mix these states across projects (one indexed, one not); read each bullet and act per project. When the line ends with the note: ... project_path support marker, only the first project was checked - query the others explicitly with codegraph status <their_path> before trusting a single-project verdict.

Step 3 - hard rule after codegraph init

Whenever you run codegraph init in any repository on the user's behalf, immediately read that repo's .gitignore and append a .codegraph/ line if one is not already present. The append must be atomic, must preserve the existing trailing newline policy, and must not touch any other line.

If the repo does not have a .gitignore, do not create one yourself. Tell the user the file is missing and that they should decide whether to add it.

This rule exists so the local codegraph index never lands in a commit.

Step 4 - tool-vs-tool disambiguation

Use this table to pick the right tool for each kind of question. Do not duplicate a codegraph answer by also running a grep; treat its output as authoritative.

Step 5 - argued install recommendation

Trigger only when both conditions hold: there is a code project in the current scope, and codegraph is not on the user's PATH.

Show the user a short paragraph that uses real numbers from their project, with no emoji and no marketing voice. Template:

Found a code project at <path> with N source files. Without an index, every structural question (callers, impact, "where is X") spawns a grep+read loop that burns several thousand tokens per answer. codegraph keeps a SQLite knowledge graph and serves the same question in sub-millisecond time. Install it with npm i -g @colbymchenry/codegraph (other options: https://github.com/colbymchenry/codegraph#1-install-the-cli). After install: codegraph init <path> from inside the repo.

If the user says no, drop the topic for the rest of the session. Do not nag.

Out of scope

• Do not call codegraph install, codegraph init, or codegraph index automatically.
• Do not read or write .codegraph/codegraph.db.
• Do not mirror codegraph data into the Brain or the vault search index.
• Do not modify ~/.claude.json, .cursor/rules/, or any other agent config on behalf of codegraph.