# Configuration Source: https://docs.agentblog.dev/reference/configuration Summary: Every field in agentblog.config.ts, its type, its default, and what breaks when it is wrong. `agentblog.config.ts` sits at your project root, next to `package.json` and `next.config.ts`, including in a `src/` layout. Exactly one module reads it: `lib/config.ts`. That is enforced by `agentblog doctor`, because `@/` maps to the root in a flat layout and to `src/` in a `src/` layout, so one import specifier cannot be right in both. With a single importer, fixing a `src/` project is a one-line change rather than a search across forty files. ## The shape [#the-shape] ```ts title="agentblog.config.ts" import { defineConfig } from '@/lib/define-config' import { mdxSource } from '@/lib/sources/mdx' export default defineConfig({ siteUrl: 'https://yourdomain.com', brand: { name: 'Your Brand', logo: { url: '/logo.png', width: 512, height: 512 }, sameAs: ['https://github.com/yourbrand'], }, source: mdxSource({ dir: 'content/blog' }), }) ``` `siteUrl`, `brand`, and `source` are required. Everything else has a default. ## Every field [#every-field] | Field | Type | Default | Notes | | ------------------ | -------------------------------------- | -------------------- | ---------------------------------------------------------------------------------- | | `siteUrl` | `string` | required | https, no trailing slash, no path. Trailing slashes are stripped before validation | | `locale` | `string` | `'en_US'` | Emitted as `og:locale` and as `inLanguage` in the structured data | | `brand.name` | `string` | required | Becomes `og:site_name` and `Organization.name` | | `brand.logo` | `{ url, width, height }` | required | `width` and `height` are required, not optional | | `brand.sameAs` | `string[]` | `[]` | Absolute URLs only. A bare handle is rejected at build time | | `source` | `ContentSource` | required | See [content sources](/reference/content-sources) | | `deployHook` | `string` | none | Required, at compile time, when the source needs a rebuild to publish | | `revalidate` | `number` | `3600` | Revalidation window in seconds for the blog routes | | `postsPerPage` | `number` | `12` | Index pagination | | `noindexTagsBelow` | `number` | `5` | Tag pages below this post count are marked `noindex` | | `indexnow` | `{ enabled, key? }` | `{ enabled: false }` | The key is 8 to 128 characters | | `verification` | `{ google?, yandex?, yahoo?, other? }` | `{}` | Maps straight onto the Next.js metadata verification fields | | `aiAccess` | `{ train?, search?, agent? }` | all `true` | Emitted into `robots.txt` | | `preflight` | `boolean` | `true` | Build-time config linting | | `trailingSlash` | `boolean` | `false` | Must match `next.config.ts` | | `defaultAuthor` | `string` | none | Author slug used when a post omits one | Unknown keys are ignored rather than rejected, so an invented field is silently dead. Change values, not structure. ## The fields worth understanding [#the-fields-worth-understanding] ### `siteUrl` [#siteurl] Every canonical link, sitemap entry, RSS link, and structured data identifier is composed from this string, so a wrong value is wrong in about forty places at once. Point it at the domain readers actually visit, never at a preview deployment. A trailing slash would produce `https://site.dev//blog/post` in every canonical, so it is stripped and the value is revalidated before use. Never build a URL by concatenating onto `config.siteUrl`. Use `absoluteUrl`, `postUrl`, `categoryUrl`, `tagUrl`, and `authorUrl` from `lib/config.ts`. They are the only code that knows your trailing-slash policy and the rule that a path ending in a file extension never takes one. ### `brand.sameAs` [#brandsameas] The single most valuable property in the file. It becomes `Organization.sameAs`, which is how a search engine or an assistant resolves "the company that published this" to a real entity rather than to a string that looks like a company name. Entity resolution is what lets a model cite you by name and attribute the claim correctly. List profiles a third party can verify: LinkedIn, Crunchbase, GitHub, YouTube, Wikidata. A bare handle is rejected, because it disambiguates nothing. ### `brand.logo` [#brandlogo] `width` and `height` are required because Google's Organization markup needs both, and a logo without dimensions is one of the most common structured data errors on the web. A relative `url` resolves against `siteUrl`. ### `deployHook` [#deployhook] Required when your content source declares that publishing needs a rebuild. Set it to a rebuild trigger URL so the publish webhook can rebuild before pinging IndexNow. In the other order you are telling a crawler to fetch a URL that was never built. You will not forget this one: the file stops type checking until it is set. ### `noindexTagsBelow` [#noindextagsbelow] Thin tag pages are the classic way a blog generates hundreds of near-empty indexable URLs and spends its own crawl budget on them. Categories are always indexable. Tags have to earn it. Set it to `0` to index every tag. ### `indexnow` [#indexnow] ```ts indexnow: { enabled: true, key: process.env.INDEXNOW_KEY } ``` The key is read from the config first and falls back to `INDEXNOW_KEY` in the environment, so the secret never has to live in this committed file. The matching `.txt` file must be served from your domain root, UTF-8, containing the key and nothing else, or every submission comes back 403. A key hosted at a subpath only authorises URLs under that subpath. `agentblog doctor --fix` writes the file for you. The limit is 10,000 URLs per request, not per day. ### `aiAccess` [#aiaccess] ```ts aiAccess: { train: true, search: true, agent: true } ``` A forward-looking seam. Three standards are converging on machine-readable AI usage preferences, and all of them attach to `robots.txt` or to HTTP headers. None is implemented yet. When one lands, this same object emits it with no change to your config file. Setting `train: false` is a real tradeoff rather than a free one. Several crawlers are multi-purpose, so opting out of training can also opt you out of the search index that would have cited you. ### `preflight` [#preflight] On by default. It reads your `next.config` off disk once per process during dev and build and warns when a required setting is missing or narrowed. It never throws and it does nothing at request time. Set it to `false` only once you know your config is correct and you want the warning gone. That is the supported way to switch it off. Deleting the preflight import from `app/blog/layout.tsx` is not, because then nothing tells you when a later edit breaks the config again. ### `trailingSlash` [#trailingslash] Must match `trailingSlash` in `next.config.ts`. The URL helpers compose canonicals from this value, so two different answers means every canonical points at a URL that immediately redirects to its other form. Search engines treat that as a redirect chain and AI crawlers frequently do not follow it at all. ## Why `defineConfig` rather than `satisfies` [#why-defineconfig-rather-than-satisfies] `defineConfig` is an identity function that exists for its type signature. It gives contextual inference, which is what lets the `deployHook` requirement depend on which content source you passed. `satisfies` checks an object against a fixed type and cannot do that. Concretely: swap `mdxSource` for a source that needs a rebuild to publish, and the file stops type checking until you supply a `deployHook`. A runtime surprise becomes a compile error, which is the highest-value thing the type layer does here. ## Validation [#validation] Your config is validated once, when `lib/config.ts` is first imported. A bad value fails the build with a message naming the key, rather than producing `undefined` inside a structured data graph three files later.