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Zig API Reference

Convert markdown links to numbered citations.

[Example](https://example.com) becomes Example[1] with [1]: <https://example.com> in the reference list. Images ![alt](url) are preserved unchanged.

Signature:

pub fn generate_citations(markdown: [:0]const u8) CitationResult

Example:

const result = generateCitations("value");

Parameters:

Name Type Required Description
markdown \[:0\]const u8 Yes The markdown

Returns: CitationResult


Create a new crawl engine with the given configuration.

If config is null, uses CrawlConfig.default(). Returns an error if the configuration is invalid.

Signature:

pub fn create_engine(config: ?CrawlConfig) CrawlError!CrawlEngineHandle

Example:

const result = try createEngine(.{});

Parameters:

Name Type Required Description
config CrawlConfig? No The configuration options

Returns: CrawlEngineHandle

Errors: Throws CrawlError.


Scrape a single URL, returning extracted page data.

Signature:

pub fn scrape(engine: CrawlEngineHandle, url: [:0]const u8) CrawlError!ScrapeResult

Example:

const result = try scrape(.{}, "value");

Parameters:

Name Type Required Description
engine CrawlEngineHandle Yes The crawl engine handle
url \[:0\]const u8 Yes The URL to fetch

Returns: ScrapeResult

Errors: Throws CrawlError.


Crawl a website starting from url, following links up to the configured depth.

Signature:

pub fn crawl(engine: CrawlEngineHandle, url: [:0]const u8) CrawlError!CrawlResult

Example:

const result = try crawl(.{}, "value");

Parameters:

Name Type Required Description
engine CrawlEngineHandle Yes The crawl engine handle
url \[:0\]const u8 Yes The URL to fetch

Returns: CrawlResult

Errors: Throws CrawlError.


Discover all pages on a website by following links and sitemaps.

Signature:

pub fn map_urls(engine: CrawlEngineHandle, url: [:0]const u8) CrawlError!MapResult

Example:

const result = try mapUrls(.{}, "value");

Parameters:

Name Type Required Description
engine CrawlEngineHandle Yes The crawl engine handle
url \[:0\]const u8 Yes The URL to fetch

Returns: MapResult

Errors: Throws CrawlError.


Execute browser actions on a single page.

Signature:

pub fn interact(engine: CrawlEngineHandle, url: [:0]const u8, actions: []const PageAction) CrawlError!InteractionResult

Example:

const result = try interact(.{}, "value", &[_]u8{});

Parameters:

Name Type Required Description
engine CrawlEngineHandle Yes The crawl engine handle
url \[:0\]const u8 Yes The URL to fetch
actions \[\]const PageAction Yes The actions

Returns: InteractionResult

Errors: Throws CrawlError.


Scrape multiple URLs concurrently.

Signature:

pub fn batch_scrape(engine: CrawlEngineHandle, urls: []const [:0]const u8) CrawlError!BatchScrapeResults

Example:

const result = try batchScrape(.{}, &[_]u8{});

Parameters:

Name Type Required Description
engine CrawlEngineHandle Yes The crawl engine handle
urls \[\]const \[:0\]const u8 Yes The urls

Returns: BatchScrapeResults

Errors: Throws CrawlError.


Crawl multiple seed URLs concurrently, each following links to configured depth.

Signature:

pub fn batch_crawl(engine: CrawlEngineHandle, urls: []const [:0]const u8) CrawlError!BatchCrawlResults

Example:

const result = try batchCrawl(.{}, &[_]u8{});

Parameters:

Name Type Required Description
engine CrawlEngineHandle Yes The crawl engine handle
urls \[\]const \[:0\]const u8 Yes The urls

Returns: BatchCrawlResults

Errors: Throws CrawlError.


Result from a single page action execution.

Field Type Default Description
actionIndex u64 Zero-based index of the action in the sequence.
actionType \[:0\]const u8 The type of action that was executed.
success bool Whether the action completed successfully.
data \[:0\]const u8? null Action-specific return data (screenshot bytes, JS return value, scraped HTML).
error \[:0\]const u8? null Error message if the action failed.

Article metadata extracted from article:* Open Graph tags.

Field Type Default Description
publishedTime \[:0\]const u8? null The article publication time.
modifiedTime \[:0\]const u8? null The article modification time.
author \[:0\]const u8? null The article author.
section \[:0\]const u8? null The article section.
tags \[\]const \[:0\]const u8 \[\] The article tags.

Result from a single URL in a batch crawl operation.

Field Type Default Description
url \[:0\]const u8 The seed URL that was crawled.
result CrawlResult? null The crawl result, if successful.
error \[:0\]const u8? null The error message, if the crawl failed.

Aggregate result of a batch crawl, exposing per-URL results plus precomputed counts.

The counts are derived once at construction so every binding language can read them as plain integer fields without re-iterating the results vector.

Field Type Default Description
results \[\]const BatchCrawlResult \[\] Per-URL crawl results, in the order seed URLs were submitted.
totalCount u64 Total number of seed URLs in the batch (equal to results.len()).
completedCount u64 Number of seed URLs whose crawl succeeded (error is null).
failedCount u64 Number of seed URLs whose crawl failed (error is Some).

Request to begin a multi-URL streaming crawl.

Wraps a set of seed URLs for delivery through the streaming-adapter binding surface. Required as a struct because alef’s streaming adapter requires a named request type — primitives are not supported.

Field Type Default Description
urls \[\]const \[:0\]const u8 \[\] The seed URLs to crawl. Each URL is followed independently up to the engine’s configured depth.

Result from a single URL in a batch scrape operation.

Field Type Default Description
url \[:0\]const u8 The URL that was scraped.
result ScrapeResult? null The scrape result, if successful.
error \[:0\]const u8? null The error message, if the scrape failed.

Aggregate result of a batch scrape, exposing per-URL results plus precomputed counts.

The counts are derived once at construction so every binding language can read them as plain integer fields without re-iterating the results vector.

Field Type Default Description
results \[\]const BatchScrapeResult \[\] Per-URL scrape results, in the order URLs were submitted.
totalCount u64 Total number of URLs in the batch (equal to results.len()).
completedCount u64 Number of URLs whose scrape succeeded (error is null).
failedCount u64 Number of URLs whose scrape failed (error is Some).

Browser fallback configuration.

Field Type Default Description
mode BrowserMode BrowserMode.Auto When to use the headless browser fallback.
backend BrowserBackend BrowserBackend.Chromiumoxide Browser backend used to render JavaScript-heavy pages.
endpoint \[:0\]const u8? null CDP WebSocket endpoint for connecting to an external browser instance.
timeout i64 30000ms Timeout for browser page load and rendering (in milliseconds when serialized).
wait BrowserWait BrowserWait.NetworkIdle Wait strategy after browser navigation.
waitSelector \[:0\]const u8? null CSS selector to wait for when wait is Selector.
extraWait i64? null Extra time to wait after the wait condition is met.
proxy ProxyConfig? null Proxy for browser fetches. Overrides CrawlConfig.proxy when set. Native backend supports http/https only (no SOCKS5).
blockUrlPatterns \[\]const \[:0\]const u8 \[\] URL patterns to block before the network request fires. Supports * wildcards. Useful for skipping ads/analytics/large images. Honored by BrowserBackend.Native; chromiumoxide ignores this field today.
evalScript \[:0\]const u8? null JavaScript snippet evaluated after navigation completes. Scraping captures the native backend result in ScrapeResult.browser.eval_result. Interactions run this script before page actions on both browser backends but do not include the script result in InteractionResult.
robotsUserAgent \[:0\]const u8? null User-agent used when fetching robots.txt. Defaults to BrowserConfig.user_agent (or crawlberg’s default) if unset. Native only.
captureNetworkEvents bool false Capture the full network event stream into the result. Default false (only the document event is captured). Native only.
sessionAffinity bool true Enable session affinity: reuse chromiumoxide Pages for same-domain requests so cookies + fingerprint + solved challenges persist. Default: true. When false, each request gets a fresh Page.

Signature:

pub fn default() BrowserConfig

Example:

const result = BrowserConfig.default();

Returns: BrowserConfig


Browser-specific extras populated when the native browser backend was used.

Available on ScrapeResult.browser when BrowserBackend.Native handled the request.

Field Type Default Description
evalResult \[:0\]const u8? null Return value of BrowserConfig.eval_script, if provided.
networkEvents \[\]const ResponseMeta \[\] Network events captured during page navigation (only populated when BrowserConfig.capture_network_events is true).
cookies \[\]const CookieInfo \[\] All non-expired cookies present in the browser’s cookie jar after navigation completes (includes both prior cookies and server Set-Cookie).

A single numbered reference in a citation list — produced by the citation extractor when content uses inline [N]-style markers.

Field Type Default Description
index u64 1-based reference number as it appears in the source text.
url \[:0\]const u8 Resolved absolute URL for this reference.
text \[:0\]const u8 Human-readable anchor text or title for the reference.

Result of citation conversion.

Field Type Default Description
content \[:0\]const u8 Markdown with links replaced by numbered citations.
references \[\]const CitationReference \[\] Numbered reference list: (index, url, text).

Content extraction and conversion configuration.

Controls how HTML is converted to the output format. Uses html-to-markdown-rs as the conversion engine for all formats (markdown, plain text, djot).

Field Type Default Description
outputFormat \[:0\]const u8 "markdown" Output format: "markdown" (default), "plain", "djot".
preprocessingPreset \[:0\]const u8 "standard" Preprocessing aggressiveness: "minimal", "standard" (default), "aggressive". - Minimal: only scripts/styles removed. - Standard: also removes nav, nav-hinted headers/footers/asides, forms. - Aggressive: removes all footers/asides unconditionally.
removeNavigation bool true Remove navigation elements (nav, breadcrumbs, menus). Default: true.
removeForms bool true Remove form elements. Default: true.
stripTags \[\]const \[:0\]const u8 \[\] HTML tag names to strip (render children only, remove the tag wrapper). Default: \["noscript"\].
preserveTags \[\]const \[:0\]const u8 \[\] HTML tag names to preserve as raw HTML in output.
excludeSelectors \[\]const \[:0\]const u8 \[\] CSS selectors for elements to exclude entirely (element + all content). Unlike strip_tags (which removes the wrapper but keeps children), excluded elements and all descendants are dropped. Supports CSS selectors: .class, #id, \[attribute\], compound selectors. Example: \[".cookie-banner", "#ad-container", "\[role='complementary'\]"\]
skipImages bool false Skip image elements in output. Default: false.
maxDepth u64? null Max DOM traversal depth. Prevents stack overflow on deeply nested HTML.
wrap bool false Enable line wrapping. Default: false.
wrapWidth u64 80 Wrap width when wrap is enabled. Default: 80.
includeDocumentStructure bool true Include document structure tree in output. Default: true.

Signature:

pub fn default() ContentConfig

Example:

const result = ContentConfig.default();

Returns: ContentConfig


Information about an HTTP cookie received from a response.

Field Type Default Description
name \[:0\]const u8 The cookie name.
value \[:0\]const u8 The cookie value.
domain \[:0\]const u8? null The cookie domain, if specified.
path \[:0\]const u8? null The cookie path, if specified.

Configuration for crawl, scrape, and map operations.

Field Type Default Description
maxDepth u64? null Maximum crawl depth (number of link hops from the start URL).
maxPages u64? null Maximum number of pages to crawl.
maxLinksPerPage u64? null Maximum links enqueued from a single page. Defaults to 10000. Bounds the work one hostile or pathological page can create; links past the cap are dropped and a warning is logged.
maxConcurrent u64? null Maximum number of concurrent requests.
respectRobotsTxt bool false Whether to respect robots.txt directives.
softHttpErrors bool false When true, HTTP-level error responses (404 NotFound, 403 Forbidden, WAF blocks) are surfaced as ScrapeResult records with the matching status_code rather than raised as CrawlError. Default false preserves the historical throw-on-error contract for direct fetches. Independently of this flag, 404s reached at the end of a redirect chain are always surfaced softly — the user opted into redirect-following, so receiving a 404 there is part of the normal flow rather than an unexpected error.
userAgent \[:0\]const u8? null Custom user-agent string.
stayOnDomain bool false Whether to restrict crawling to the same domain.
allowSubdomains bool false Whether to allow subdomains when stay_on_domain is true.
includePaths \[\]const \[:0\]const u8 \[\] Regex patterns for paths to include during crawling.
excludePaths \[\]const \[:0\]const u8 \[\] Regex patterns for paths to exclude during crawling.
customHeaders std.StringHashMap(\[:0\]const u8) {} Custom HTTP headers to send with each request.
requestTimeout i64 30000ms Timeout for individual HTTP requests (in milliseconds when serialized).
rateLimitMs u64? null Per-domain rate limit in milliseconds. When set, enforces a minimum delay between requests to the same domain. Defaults to 200ms when null.
maxRedirects u64 10 Maximum number of redirects to follow.
retryCount u64 0 Number of retry attempts for failed requests.
retryCodes \[\]const u16 \[\] HTTP status codes that should trigger a retry.
cookiesEnabled bool false Whether to enable cookie handling.
auth AuthConfig? null Authentication configuration.
maxBodySize u64? null Maximum response body size in bytes.
removeTags \[\]const \[:0\]const u8 \[\] CSS selectors for tags to remove from HTML before processing.
content ContentConfig Content extraction and conversion configuration.
mapLimit u64? null Maximum number of URLs to return from a map operation.
mapSearch \[:0\]const u8? null Search filter for map results (case-insensitive substring match on URLs).
downloadAssets bool false Whether to download assets (CSS, JS, images, etc.) from the page.
assetTypes \[\]const AssetCategory \[\] Filter for asset categories to download.
maxAssetSize u64? null Maximum size in bytes for individual asset downloads.
browser BrowserConfig Browser configuration.
proxy ProxyConfig? null Proxy configuration for HTTP requests.
userAgents \[\]const \[:0\]const u8 \[\] List of user-agent strings for rotation. If non-empty, overrides user_agent.
captureScreenshot bool false Whether to capture a screenshot when using the browser. Only supported by scrape() with BrowserBackend.Chromiumoxide and BrowserMode.Always or Stealth. A screenshot is 100–500 KB of PNG per page, so crawl() does not carry screenshots in CrawlPageResult/CrawlResult at all — a multi-thousand-page crawl holding one per page in memory is not a safe default. Setting this with any other configuration (a different backend, BrowserMode.Auto/Never, or during crawl()) has no effect and logs a warning rather than silently doing nothing.
followDocumentUrls bool false Re-enqueue discovered LinkType.Document URLs into the crawl frontier so the crawl follows links from document pages (PDFs, etc.) as it would from HTML pages. Default: false (documents terminate at materialisation).
documentUrlDepth u32? null Maximum document-depth (from the seed URL through document links only) when follow_document_urls is true. null means inherit max_depth. Independent of max_depth: a document URL is enqueued only if BOTH the outer max_depth and (if set) document_url_depth permit it.
downloadDocuments bool true Whether to download non-HTML documents (PDF, DOCX, images, code, etc.) instead of skipping them. Defaults to true — unlike download_assets and capture_screenshot, which default to false.
documentMaxSize u64? 52428800 Maximum size in bytes for document downloads. Defaults to 50 MB.
documentMimeTypes \[\]const \[:0\]const u8 \[\] Allowlist of MIME types to download. If empty, uses built-in defaults.
documentOutputDir \[:0\]const u8? null Directory to stream downloaded document bytes into instead of holding them in memory on DownloadedDocument.content. When set, content is left empty and DownloadedDocument.content_path is populated with <dir>/<content_hash>.<ext>. null (default) preserves today’s in-memory-only behavior. Has no effect on wasm32, which has no filesystem — use document_content_encoding there instead.
documentContentEncoding DocumentContentEncoding? null Opt-in encoding that duplicates DownloadedDocument.content into a serializable field for language bindings that need the bytes in-memory (content itself is alef(skip)ed). null (default) means no encoding is produced. Independent of document_output_dir — set both to get a file on disk and an in-memory copy.
warcOutput \[:0\]const u8? null Path to write WARC output. If null, WARC output is disabled.
browserProfile \[:0\]const u8? null Named browser profile for persistent sessions (cookies, localStorage). Chromiumoxide backend only. The native backend runs an in-process JavaScript engine with no Chrome process and therefore no profile directory, so this is ignored there and logs a warning. It is also ignored — with a warning — when a shared browser pool is in use (the pool launches before any per-crawl config exists) or when connecting to an external CDP endpoint whose process crawlberg does not own.
saveBrowserProfile bool false Whether to save changes back to the browser profile on exit.
ssrf SsrfPolicy SSRF policy for outbound network requests. Default: deny private networks, allow http/https only, max 5 redirects. deny_private, allowlist and max_redirects are exposed to all language bindings. scheme_allowlist stays Rust-only — see SsrfPolicy. wasm32 (including Node.js): deny_private does not stop hostname-based requests. There is no DNS resolution on this target, so only a literal IP host is checked against the policy — a domain name is always permitted, regardless of deny_private. Under Node, where fetch enforces no CORS, this means a service embedding the wasm binding can be driven to internal hosts by domain name even with deny_private = true. Enforce egress restrictions at the network layer for that deployment target; do not rely on this field. See crawlberg.net.validate_url.
ssrfDenyPrivateExplicit bool? null Pins SsrfPolicy.deny_private to a caller-chosen value, bypassing the CRAWLBERG_ALLOW_PRIVATE_NETWORK operator override entirely for this config. ssrf.deny_private is a plain, always-serialized bool: several alef-generated bindings construct SsrfPolicy.default() (hardcoding deny_private: true) whenever their caller never touches SSRF settings at all, so true on that field alone cannot distinguish “the caller wants private networks denied” from “the binding’s own structural default landed on true”. The environment variable exists precisely to resolve that ambiguity in the common case by treating any true as inconclusive and deferring to the operator. Set this field when that default-deferral is wrong for your call — e.g. a test that must prove deny_private: true still denies even while the operator has set CRAWLBERG_ALLOW_PRIVATE_NETWORK suite-wide for every other call. null (default) preserves today’s behavior: the environment variable may still flip ssrf.deny_private to false. Some(value) pins ssrf.deny_private to value and the environment variable is not consulted for this config.

Signature:

pub fn default() CrawlConfig

Example:

const result = CrawlConfig.default();

Returns: CrawlConfig

Validate the configuration, returning an error if any values are invalid.

Signature:

pub fn validate(self: *const CrawlConfig) CrawlError!void

Example:

try instance.validate();

Returns: No return value.

Errors: Throws CrawlError.


Opaque handle to a configured crawl engine.

Constructed via create_engine with an optional CrawlConfig. Default implementations for all pluggable components are used internally.


The result of crawling a single page during a crawl operation.

Field Type Default Description
url \[:0\]const u8 The original URL of the page.
normalizedUrl \[:0\]const u8 The normalized URL of the page.
statusCode u16 The HTTP status code of the response.
contentType \[:0\]const u8 The Content-Type header value.
html \[:0\]const u8 The HTML body of the response.
bodySize u64 The size of the response body in bytes.
metadata PageMetadata Extracted metadata from the page.
links \[\]const LinkInfo \[\] Links found on the page.
images \[\]const ImageInfo \[\] Images found on the page.
feeds \[\]const FeedInfo \[\] Feed links found on the page.
jsonLd \[\]const JsonLdEntry \[\] JSON-LD entries found on the page.
depth u64 The depth of this page from the start URL.
stayedOnDomain bool Whether this page is on the same domain as the start URL.
wasSkipped bool Whether this page was skipped (binary or PDF content).
isPdf bool Whether the content is a PDF.
detectedCharset \[:0\]const u8? null The detected character set encoding.
markdown MarkdownResult? null Markdown conversion of the page content.
extractedData \[:0\]const u8? null Structured data extracted by LLM. Populated when extraction is configured.
extractionMeta ExtractionMeta? null Metadata about the LLM extraction pass (cost, tokens, model).
downloadedDocument DownloadedDocument? null Downloaded non-HTML document (PDF, DOCX, image, code, etc.).
browserUsed bool Whether the browser fallback was used to fetch this page.

The result of a multi-page crawl operation.

Field Type Default Description
pages \[\]const CrawlPageResult \[\] The list of crawled pages.
finalUrl \[:0\]const u8 The final URL after following redirects.
redirectCount u64 The number of redirects followed.
wasSkipped bool Whether any page was skipped during crawling.
error \[:0\]const u8? null An error message, if the crawl encountered an issue.
cookies \[\]const CookieInfo \[\] Cookies collected during the crawl.
stayedOnDomain bool Whether all crawled pages stayed on the same domain as the start URL.
browserUsed bool Whether the browser fallback was used for any page in this crawl.

Returns the count of unique normalized URLs encountered during crawling.

Computed from pages (not the deprecated normalized_urls field) so it is correct across every binding that reconstructs CrawlResult from pages alone. In streaming mode pages is empty, so this returns 0 on the opaque-handle (C/Go/C#/Zig/Dart) path where it previously counted streamed pages — a known, accepted cost of making the other ten binding families correct.

Signature:

pub fn uniqueNormalizedUrls(self: *const CrawlResult) u64

Example:

const result = instance.uniqueNormalizedUrls();

Returns: u64


Request to begin a single-URL streaming crawl.

Wraps a single seed URL for delivery through the streaming-adapter binding surface. Required as a struct because alef’s streaming adapter requires a named request type — primitives are not supported.

Field Type Default Description
url \[:0\]const u8 The seed URL to crawl.

A downloaded asset from a page.

Field Type Default Description
url \[:0\]const u8 The original URL of the asset.
contentHash \[:0\]const u8 The SHA-256 content hash of the asset.
mimeType \[:0\]const u8? null The MIME type from the Content-Type header.
size u64 The size of the asset in bytes.
assetCategory AssetCategory AssetCategory.Image The category of the asset.
htmlTag \[:0\]const u8? null The HTML tag that referenced this asset (e.g., “link”, “script”, “img”).

A downloaded non-HTML document (PDF, DOCX, image, code file, etc.).

When the crawler encounters non-HTML content and download_documents is enabled, it downloads the raw bytes and populates this struct instead of skipping the resource.

Field Type Default Description
url \[:0\]const u8 The URL the document was fetched from.
mimeType \[:0\]const u8 The MIME type from the Content-Type header.
size u64 Size of the document in bytes.
filename \[:0\]const u8? null Filename extracted from Content-Disposition or URL path.
contentHash \[:0\]const u8 SHA-256 hex digest of the content.
headers std.StringHashMap(\[:0\]const u8) {} Selected response headers.
truncated bool True when content (or the file at content_path) was truncated to document_max_size; size still reports the original, untruncated length.
contentPath \[:0\]const u8? null Filesystem path the document was streamed to when document_output_dir was set. content is empty in memory when this is populated.
contentBase64 \[:0\]const u8? null Base64-encoded copy of content, populated only when document_content_encoding was set to Base64.

Metadata about an LLM extraction pass.

Field Type Default Description
cost f64? null Estimated cost of the LLM call in USD.
promptTokens u64? null Number of prompt (input) tokens consumed.
completionTokens u64? null Number of completion (output) tokens generated.
model \[:0\]const u8? null The model identifier used for extraction.
chunksProcessed u64 Number of content chunks sent to the LLM.

Information about a favicon or icon link.

Field Type Default Description
url \[:0\]const u8 The icon URL.
rel \[:0\]const u8 The rel attribute (e.g., “icon”, “apple-touch-icon”).
sizes \[:0\]const u8? null The sizes attribute, if present.
mimeType \[:0\]const u8? null The MIME type, if present.

Information about a feed link found on a page.

Field Type Default Description
url \[:0\]const u8 The feed URL.
title \[:0\]const u8? null The feed title, if present.
feedType FeedType FeedType.Rss The type of feed.

A heading element extracted from the page.

Field Type Default Description
level u8 The heading level (1-6).
text \[:0\]const u8 The heading text content.

An hreflang alternate link entry.

Field Type Default Description
lang \[:0\]const u8 The language code (e.g., “en”, “fr”, “x-default”).
url \[:0\]const u8 The URL for this language variant.

Information about an image found on a page.

Field Type Default Description
url \[:0\]const u8 The image URL.
alt \[:0\]const u8? null The alt text, if present.
width u32? null The width attribute, if present and parseable.
height u32? null The height attribute, if present and parseable.
source ImageSource ImageSource.Img The source of the image reference.

Result of executing a sequence of page interaction actions.

Field Type Default Description
actionResults \[\]const ActionResult \[\] Results from each executed action.
finalHtml \[:0\]const u8 Final page HTML after all actions completed.
finalUrl \[:0\]const u8 Final page URL (may have changed due to navigation).
screenshotBase64 \[:0\]const u8? null Base64-encoded PNG screenshot taken after all actions. Populated only when a PageAction.Screenshot action actually ran, so callers that never request a screenshot do not pay the encoding cost.

A JSON-LD structured data entry found on a page.

Field Type Default Description
schemaType \[:0\]const u8 The @type value from the JSON-LD object.
name \[:0\]const u8? null The name value, if present.
raw \[:0\]const u8 The raw JSON-LD string.

Information about a link found on a page.

Field Type Default Description
url \[:0\]const u8 The resolved URL of the link.
text \[:0\]const u8 The visible text of the link.
linkType LinkType LinkType.Internal The classification of the link.
rel \[:0\]const u8? null The rel attribute value, if present.
nofollow bool Whether the link has rel="nofollow".

The result of a map operation, containing discovered URLs.

Field Type Default Description
urls \[\]const SitemapUrl \[\] The list of discovered URLs.

Rich markdown conversion result from HTML processing.

Field Type Default Description
content \[:0\]const u8 Converted markdown text.
documentStructure \[:0\]const u8? null Structured document tree with semantic nodes.
tables \[\]const \[:0\]const u8 \[\] Extracted tables with structured cell data.
warnings \[\]const \[:0\]const u8 \[\] Non-fatal processing warnings.
citations bool Whether citation conversion was applied and produced at least one reference. true when the markdown contained inline links that were converted to numbered citation references. The converted content (with \[N\] markers) is available in content; the full reference list is accessible via generate_citations if needed separately.
fitContent \[:0\]const u8? null Content-filtered markdown optimized for LLM consumption.

Metadata extracted from an HTML page’s <meta> tags and <title> element.

Field Type Default Description
title \[:0\]const u8? null The page title from the <title> element.
description \[:0\]const u8? null The meta description.
canonicalUrl \[:0\]const u8? null The canonical URL from <link rel="canonical">.
keywords \[:0\]const u8? null Keywords from <meta name="keywords">.
author \[:0\]const u8? null Author from <meta name="author">.
viewport \[:0\]const u8? null Viewport content from <meta name="viewport">.
themeColor \[:0\]const u8? null Theme color from <meta name="theme-color">.
generator \[:0\]const u8? null Generator from <meta name="generator">.
robots \[:0\]const u8? null Robots content from <meta name="robots">.
htmlLang \[:0\]const u8? null The lang attribute from the <html> element.
htmlDir \[:0\]const u8? null The dir attribute from the <html> element.
ogTitle \[:0\]const u8? null Open Graph title.
ogType \[:0\]const u8? null Open Graph type.
ogImage \[:0\]const u8? null Open Graph image URL.
ogDescription \[:0\]const u8? null Open Graph description.
ogUrl \[:0\]const u8? null Open Graph URL.
ogSiteName \[:0\]const u8? null Open Graph site name.
ogLocale \[:0\]const u8? null Open Graph locale.
ogVideo \[:0\]const u8? null Open Graph video URL.
ogAudio \[:0\]const u8? null Open Graph audio URL.
ogLocaleAlternates \[\]const \[:0\]const u8? \[\] Open Graph locale alternates.
twitterCard \[:0\]const u8? null Twitter card type.
twitterTitle \[:0\]const u8? null Twitter title.
twitterDescription \[:0\]const u8? null Twitter description.
twitterImage \[:0\]const u8? null Twitter image URL.
twitterSite \[:0\]const u8? null Twitter site handle.
twitterCreator \[:0\]const u8? null Twitter creator handle.
dcTitle \[:0\]const u8? null Dublin Core title.
dcCreator \[:0\]const u8? null Dublin Core creator.
dcSubject \[:0\]const u8? null Dublin Core subject.
dcDescription \[:0\]const u8? null Dublin Core description.
dcPublisher \[:0\]const u8? null Dublin Core publisher.
dcDate \[:0\]const u8? null Dublin Core date.
dcType \[:0\]const u8? null Dublin Core type.
dcFormat \[:0\]const u8? null Dublin Core format.
dcIdentifier \[:0\]const u8? null Dublin Core identifier.
dcLanguage \[:0\]const u8? null Dublin Core language.
dcRights \[:0\]const u8? null Dublin Core rights.
article ArticleMetadata? null Article metadata from article:* Open Graph tags.
hreflangs \[\]const HreflangEntry? \[\] Hreflang alternate links.
favicons \[\]const FaviconInfo? \[\] Favicon and icon links.
headings \[\]const HeadingInfo? \[\] Heading elements (h1-h6).
wordCount u64? null Computed word count of the page body text.

Proxy configuration for HTTP requests.

Field Type Default Description
url \[:0\]const u8 Proxy URL (e.g. “http://proxy:8080", “socks5://proxy:1080”).
username \[:0\]const u8? null Optional username for proxy authentication.
password \[:0\]const u8? null Optional password for proxy authentication.

Response metadata extracted from HTTP headers.

Field Type Default Description
etag \[:0\]const u8? null The ETag header value.
lastModified \[:0\]const u8? null The Last-Modified header value.
cacheControl \[:0\]const u8? null The Cache-Control header value.
server \[:0\]const u8? null The Server header value.
xPoweredBy \[:0\]const u8? null The X-Powered-By header value.
contentLanguage \[:0\]const u8? null The Content-Language header value.
contentEncoding \[:0\]const u8? null The Content-Encoding header value.

The result of a single-page scrape operation.

Field Type Default Description
statusCode u16 The HTTP status code of the response.
finalUrl \[:0\]const u8 The final URL after following all redirects.
contentType \[:0\]const u8 The Content-Type header value.
html \[:0\]const u8 The HTML body of the response.
bodySize u64 The size of the response body in bytes.
metadata PageMetadata Extracted metadata from the page.
links \[\]const LinkInfo \[\] Links found on the page.
images \[\]const ImageInfo \[\] Images found on the page.
feeds \[\]const FeedInfo \[\] Feed links found on the page.
jsonLd \[\]const JsonLdEntry \[\] JSON-LD entries found on the page.
isAllowed bool Whether the URL is allowed by robots.txt.
crawlDelay u64? null The crawl delay from robots.txt, in seconds.
noindexDetected bool Whether a noindex directive was detected.
nofollowDetected bool Whether a nofollow directive was detected.
xRobotsTag \[:0\]const u8? null The X-Robots-Tag header value, if present.
isPdf bool Whether the content is a PDF.
wasSkipped bool Whether the page was skipped (binary or PDF content).
detectedCharset \[:0\]const u8? null The detected character set encoding.
authHeaderSent bool Whether an authentication header was sent with the request.
responseMeta ResponseMeta? null Response metadata extracted from HTTP headers.
assets \[\]const DownloadedAsset \[\] Downloaded assets from the page.
jsRenderHint bool Whether the page content suggests JavaScript rendering is needed.
browserUsed bool Whether the browser fallback was used to fetch this page.
markdown MarkdownResult? null Markdown conversion of the page content.
extractedData \[:0\]const u8? null Structured data extracted by LLM. Populated when extraction is configured.
extractionMeta ExtractionMeta? null Metadata about the LLM extraction pass (cost, tokens, model).
screenshotBase64 \[:0\]const u8? null Base64-encoded PNG screenshot of the page. Populated only when CrawlConfig.capture_screenshot was enabled for this request, so callers that never requested a screenshot do not pay the encoding cost.
downloadedDocument DownloadedDocument? null Downloaded non-HTML document (PDF, DOCX, image, code, etc.).
browser BrowserExtras? null Browser-specific extras (eval result, network events, cookies). Only populated when BrowserBackend.Native was used for this request.

A URL entry from a sitemap.

Field Type Default Description
url \[:0\]const u8 The URL.
lastmod \[:0\]const u8? null The last modification date, if present.
changefreq \[:0\]const u8? null The change frequency, if present.
priority \[:0\]const u8? null The priority, if present.

SSRF policy configuration.

Field Type Default Description
denyPrivate bool true If true, reject URLs that resolve to private/metadata IP ranges.
allowlist \[\]const HostMatcher \[\] Hostnames and IP ranges permitted regardless of deny_private. The allowlist is an override of deny_private, not an intersection with it. Precedence, in order: 1. deny_private == false permits everything; the allowlist is not consulted. 2. A hostname matching an Exact or Suffix entry is permitted immediately, before DNS resolution — so the deny-list is never applied to it. This trusts the host string: a name that resolves into private space is still permitted. 3. A literal or resolved IP inside a Cidr entry is permitted even though it is in the default deny-list. 4. Otherwise the default deny-list decides. An empty allowlist therefore denies nothing by itself — it simply leaves deny_private and the deny-list in sole control.
maxRedirects u8 5 Maximum number of HTTP redirects to follow during validation.

Signature:

pub fn default() SsrfPolicy

Example:

const result = SsrfPolicy.default();

Returns: SsrfPolicy

Create a policy from environment variables.

On native platforms, reads CRAWLBERG_ALLOW_PRIVATE_NETWORK — if set to “1” or “true” (case-insensitive), sets deny_private = false. Otherwise, defaults to deny_private = true.

On wasm32 targets (browser/Node.js), environment variables are not accessible to the compiled module. Defaults to deny_private = false because:

  • Outbound requests in a browser go through the fetch API, which enforces its own network policies.
  • Rust-side SSRF checking is unenforceable and redundant in a wasm32 context.
  • For testing and localhost access, the host’s network sandbox is the enforcing boundary.

Node.js caveat: deny_private (whatever its value) has no effect on hostname-based requests under wasm32. There is no DNS resolution on this target, so validate_url only ever checks a literal IP host; a domain name falls straight through to Ok(()). In a browser this is covered by same-origin/CORS. Node’s fetch enforces no CORS, so a Node service embedding this wasm module can be driven to internal hosts by domain name even though deny_private = true. Do not rely on this policy to stop that in Node — enforce egress restrictions (network policy, firewall, proxy allowlist) outside the process.

Signature:

pub fn fromEnv() SsrfPolicy

Example:

const result = SsrfPolicy.fromEnv();

Returns: SsrfPolicy


When to use the headless browser fallback.

Value Description
Auto Automatically detect when JS rendering is needed and fall back to browser.
Always Always use the browser for every request.
Never Never use the browser fallback.
Stealth Always use the browser with all stealth surfaces enabled. Behaves like Always for escalation purposes (every request is routed through the browser tier), but additionally enables: - browser JavaScript stealth patches - native-backend TLS fingerprint spoofing - stealth-aware default user-agent when no explicit UA is set - 1920×1080 viewport override Use this instead of setting the now-removed BrowserConfig.stealth boolean field.

Wait strategy for browser page rendering.

Value Description
NetworkIdle Wait until network activity is idle.
Selector Wait for a specific CSS selector to appear in the DOM.
Fixed Wait for a fixed duration after navigation.

Browser backend used for JavaScript rendering.

Value Description
Chromiumoxide Existing Chromium/CDP backend powered by chromiumoxide.
Native Crawlberg-owned native browser backend derived from Obscura.

Opt-in encoding applied to a downloaded document’s bytes for callers who need the content available in a serializable field rather than reading it from disk.

null (the CrawlConfig.document_content_encoding default) produces neither — unlike screenshots, base64-encoding a document by default would duplicate an already up-to-document_max_size buffer (50 MB default) in memory per document.

Value Description
Base64 Populate DownloadedDocument.content_base64 with a base64-encoded copy.

Authentication configuration.

Value Description
Basic HTTP Basic authentication. — Fields: username: \[:0\]const u8, password: \[:0\]const u8
Bearer Bearer token authentication. — Fields: token: \[:0\]const u8
Header Custom authentication header. — Fields: name: \[:0\]const u8, value: \[:0\]const u8

The classification of a link.

Value Description
Internal A link to the same domain.
External A link to a different domain.
Anchor A fragment-only link (e.g., #section).
Document A link to a downloadable document (PDF, DOC, etc.).

The source of an image reference.

Value Description
Img An <img> tag.
PictureSource A <source> tag inside <picture>.
OgImage An og:image meta tag.
TwitterImage A twitter:image meta tag.

The type of a feed (RSS, Atom, or JSON Feed).

Value Description
Rss RSS feed.
Atom Atom feed.
JsonFeed JSON Feed.

The category of a downloaded asset.

Value Description
Document A document file (PDF, DOC, etc.).
Image An image file.
Audio An audio file.
Video A video file.
Font A font file.
Stylesheet A CSS stylesheet.
Script A JavaScript file.
Archive An archive file (ZIP, TAR, etc.).
Data A data file (JSON, XML, CSV, etc.).
Other An unrecognized asset type.

An event emitted during a streaming crawl operation.

Not available on wasm32 targets — streaming requires native concurrency primitives (tokio channels, JoinSet) that are not supported on wasm32.

Delivered to bindings through each target’s native streaming idiom.

Value Description
Page A single page has been crawled. — Fields: result: CrawlPageResult
Error An error occurred while crawling a URL. — Fields: url: \[:0\]const u8, error: \[:0\]const u8
Complete The crawl has completed. — Fields: pagesCrawled: u64

A single page interaction action.

Actions are serialized with a type tag using camelCase naming, except ExecuteJs which is explicitly renamed to "executeJs".

Value Description
Click Click on an element matching the given CSS selector. — Fields: selector: \[:0\]const u8
TypeText Type text into an element matching the given CSS selector. — Fields: selector: \[:0\]const u8, text: \[:0\]const u8
Press Press a keyboard key (e.g. “Enter”, “Tab”, “Escape”). — Fields: key: \[:0\]const u8
Scroll Scroll the page or a specific element. — Fields: direction: ScrollDirection, selector: \[:0\]const u8, amount: i64
Wait Wait for a duration or for an element to appear. — Fields: milliseconds: i64, selector: \[:0\]const u8
Screenshot Take a screenshot of the current page. — Fields: fullPage: bool
ExecuteJs Execute arbitrary JavaScript in the page context. Safety: The script runs with full page privileges in the browser context. Only execute scripts from trusted sources. — Fields: script: \[:0\]const u8
Scrape Scrape the current page HTML.

Direction for a scroll action.

Value Description
Up Scroll upward.
Down Scroll downward.

Hostname/IP allowlist matcher for SSRF policy.

Serializes as an internally-tagged object so each variant is distinguishable on the wire and round-trips losslessly:

{"type": "exact", "value": "api.example.com"}
{"type": "suffix", "value": ".example.com"}
{"type": "cidr", "value": "10.0.0.0/8"}

A bare JSON string is still accepted on deserialization and resolves to Exact, preserving configs written against the previous untagged representation.

Exact: HostMatcher.Exact

Value Description
Exact Exact hostname match (case-insensitive). — Fields: value: \[:0\]const u8
Suffix Suffix match: “.xberg.io” matches “api.xberg.io” and “xberg.io”. — Fields: value: \[:0\]const u8
Cidr CIDR match: “10.0.0.0/8” matches IP addresses in that range. — Fields: value: \[:0\]const u8

Errors that can occur during crawling, scraping, or mapping operations.

Variant Description
NotFound The requested page was not found (HTTP 404).
Unauthorized The request was unauthorized (HTTP 401).
Forbidden The request was forbidden (HTTP 403).
WafBlocked The request was blocked by a WAF or bot protection (HTTP 403 with WAF indicators). vendor is the lowercase identifier of the detected WAF (e.g. “cloudflare”, “datadome”). When the engine cannot identify the vendor, it uses “unknown”. message is the freeform description for logs and human readers. The stable error tag remains forbidden: waf/blocked: MESSAGE so existing log-grep patterns and cross-language bindings continue to work; vendor is surfaced separately for structured consumers.
Timeout The request timed out.
RateLimited The request was rate-limited (HTTP 429).
ServerError A server error occurred (HTTP 5xx).
BadGateway A bad gateway error occurred (HTTP 502).
Gone The resource is permanently gone (HTTP 410).
Connection A connection error occurred.
Dns A DNS resolution error occurred.
Ssl An SSL/TLS error occurred.
DataLoss Data was lost or truncated during transfer.
BrowserError The browser failed to launch, connect, or navigate.
BrowserTimeout The browser page load or rendering timed out.
InvalidConfig The provided configuration is invalid.
Unsupported The requested capability is not supported by the active backend or build.
SsrfPolicyViolation A URL was rejected by SSRF policy (private IP, metadata, disallowed scheme, etc).
Other An unclassified error occurred.

SSRF validation error.

Variant Description
DeniedByPolicy URL denied by SSRF policy: private IP, metadata IP, etc.
NotOnAllowlist Host not on allowlist when an allowlist is configured.
InvalidCidr Allowlist entry is not a parseable CIDR block.
DnsResolutionFailed DNS resolution failed for hostname.
InvalidUrl Invalid URL format.
DisallowedScheme URL scheme not in allowlist (e.g., ftp:// when only http/https allowed).
TooManyRedirects Too many HTTP redirects encountered during validation.