In r-lib/depends: Package Dependency Resolution and Downloads

built: the Built field from the DESCRIPTION file of binary packages, for which this information is available.
cache_status: whether the package file is in the package cache. It is NA for installed:: package refs.
dep_types: character vector of dependency types that were considered for this package. (This is a list column.)
deps: dependencies of the package, in a data frame. See "Package dependency tables" below.
direct: whether this package (ref, really) was directly specified, or added as a dependency.
error: this is a list column that contains error objects for the refs that pkgdepends failed to resolve.
filesize: the file size in bytes, or NA if this information is not available.
license: license of the package, or NA if not available.
md5sum: MD5 checksum of the package file, if available, or NA if not.
metadata: a named character vector. These fields will be (should be) added to the installed DESCRIPTION file of the package.
mirror: URL of the CRAN(-like) mirror site where the metadata was obtained from. It is NA for non-CRAN-like sources, e.g. local files, installed packages, GitHub, etc.
needscompilation: whether the package needs compilation.
package: package name.
priority: this is "base" for base packages, "recommended" for recommended packages, and NA otherwise.
ref: package reference.
remote: the parsed remote_ref objects, see [parse_pkg_refs()]. This is a list column.
repodir: the directory where this package should be in a CRAN-like repository.
sha256: SHA256 hash of the package file, if available, otherwise NA.
sources: URLs where this package can be downloaded from. This is not necessarily a URL that you can download with a HTTP client. E.g. for local:: refs it is a path, and for git:: refs it is a URL for git. It is a zero length vector for installed:: refs.
status: status of the dependency resolution, "OK" or "FAILED".
target: path where this package should be saved in a CRAN-repository.
type: ref type.
version: package version.

Additional columns might be present. They are either used internally or they are experimental. They might be removed or changed at any time.

All columns are of type character, except for direct (logical), needscompilation (logical), filesize (integer), deps (list column, see "Package dependency tables" below), sources (list of character vectors), remote (list), error (list), metadata (list), dep_types (list).