> ## Documentation Index
> Fetch the complete documentation index at: https://docs.langchain.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Code mode

> Generate and maintain repository documentation for coding agents with OpenWiki

Code mode builds a repository wiki in `openwiki/` with durable details such as architecture, integrations, and workflows. Coding agents use that wiki as context so they can work in the package more efficiently, with less rediscovery and fewer tokens. Humans can read the same Markdown, but agents are the primary audience. Agents discover the wiki through pointers OpenWiki adds to `AGENTS.md` and `CLAUDE.md`.

`openwiki`, `openwiki --init`, and `openwiki --update` run in code mode. You can also pass the mode explicitly:

```bash theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
openwiki code --init
openwiki code --update
openwiki code --update --print
```

## What code mode produces

After a successful init or update, the repository typically includes:

* **`openwiki/`**: Generated Markdown wiki (quickstart, architecture, operations, and related topics)
* **`openwiki/INSTRUCTIONS.md`**: User-authored brief for scope and priorities. OpenWiki reads it on init and update. Edit it yourself, or ask OpenWiki in chat to change it; normal `--init` and `--update` runs do not rewrite it
* **`openwiki/.last-update.json`**: Metadata for the last successful documentation change (used to avoid no-op update loops)
* **`AGENTS.md` / `CLAUDE.md`**: OpenWiki inserts or refreshes an `<!-- OPENWIKI:START -->` … `<!-- OPENWIKI:END -->` block that tells coding agents when to consult the wiki. Existing content outside that block is left untouched

## Markdown output

OpenWiki's durable output is Markdown (OKF), not a static HTML site. To explore the wiki in a browser, run [`openwiki visualize`](/oss/openwiki/visualize). The command serves a viewer only on your local machine (`127.0.0.1`). To host a human-readable site, render the Markdown with another tool (for example GitHub Pages, MkDocs, or an OKF-compatible viewer).

## Open Knowledge Format

OpenWiki emits [Google Open Knowledge Format (OKF)](https://cloud.google.com/blog/products/data-analytics/how-the-open-knowledge-format-can-improve-data-sharing) v0.1 bundles in both code and personal modes:

* A **concept** is an ordinary wiki Markdown page (one topic file). Every concept has YAML front matter with a non-empty `type`; other standard fields are optional
* `index.md` and `log.md` are **reserved** scaffolding files, not concepts: `index.md` is a directory listing, and `log.md` is update history. Nested indexes contain no front matter, while the root index declares `okf_version: "0.1"`
* Valid `timestamp` values and producer-defined extension fields are accepted and preserved during updates and migrations
* Standard Markdown links between concept documents express relationships

## Ignore paths

Create a `.openwikiignore` file in the repository root to keep generated docs from reading or describing private, generated, or irrelevant paths. The syntax supports comments, blank lines, `*` and `**` globs, directory rules, and `!` negation:

```txt theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
secrets/
*.log
!logs/keep.log
```

When `.openwikiignore` has active rules, OpenWiki filters filesystem discovery and restricts shell execute so ignored paths stay out of the run.

<Note>
  This is a read boundary: ignored paths are never read, scanned, or reproduced in the generated docs. It does not guarantee a topic will never be mentioned, because the agent may still infer an ignored area from other allowed evidence such as tests, the README, commit messages, or the existing wiki.
</Note>

## Diagrams

OpenWiki embeds Mermaid diagrams where they clarify a concept better than prose. After each run, it validates Mermaid fences. A diagram that fails validation is converted in place to a plain `text` fence with a short comment, then repaired on a later `--update` run when possible.

For validation that matches GitHub rendering more closely, install the Mermaid parser wherever you run OpenWiki:

```bash theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
npm install mermaid jsdom
```

When the parser is present, OpenWiki uses it. When it is absent, OpenWiki falls back to a lightweight check. Diagram generation works either way.

## Customize the wiki brief

Edit `openwiki/INSTRUCTIONS.md` to steer scope, priorities, and preferred writing conventions for repository documentation (for example tone, terminology, and what to emphasize or skip). OpenWiki reads this file on init and update runs. You can also ask OpenWiki in chat to revise the brief:

```bash theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
openwiki "Update openwiki/INSTRUCTIONS.md to prioritize the public API and skip internal tooling"
```

Normal `--init` and `--update` runs do not rewrite this file.

## See also

* [Visualize your wiki](/oss/openwiki/visualize)
* [Automate updates](/oss/openwiki/automate-updates)
* [Customize OpenWiki](/oss/openwiki/customize)
* [Personal mode](/oss/openwiki/personal-mode)

***

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