Javadocs.dev
Developer tools Listed by MCPBayJavadoc and source code of any Maven Central library, by artifact, version and symbol
By: James Ward
The connection URL lives in your cabinet. Use "Add" above, then open "My MCPs" — the address for your AI client appears there.
About
Javadocs.dev serves the Javadoc and sources of any library published to Maven Central. Its MCP server lets an assistant look up real JVM APIs instead of guessing method signatures.
Tools:
- search_artifacts — find Maven artifacts by name.
- get_latest_version — latest published version of an artifact.
- get_javadoc_index, list_javadoc_symbols, get_javadoc_symbol — browse and read the Javadoc of classes and methods.
- list_source_files, get_source_file — read the actual source code of a library version.
- symbol_to_artifact — find which artifact contains a given class.
Typical use: "Which version of jackson-databind is latest, and what is the exact signature of ObjectMapper.readValue for TypeReference?"
Who it is for: Java, Kotlin and Scala developers.
Notes: free, open source, no account needed.
Tools (8)
get_javadoc_indexFetches the rendered Javadoc/Scaladoc index page for a specific Maven Central artifact version, converted to plain text/markdown. Useful for orienting yourself in an unfamiliar library: it lists the top-level packages, modules, and (for Scaladoc) often a curated overview. Use this before drilling into specific symbols. Works against the live Maven Central catalog — you do not need to download the javadoc jar.
get_javadoc_symbolReads one Javadoc/Scaladoc page from a Maven Central artifact, already converted to plain text/markdown so you don't have to parse HTML. Pass the `link` value returned by list_javadoc_symbols. Use this when you need to know what a class, method, or field does and what its parameters mean for any library on Maven Central — without downloading or unzipping the javadoc jar yourself.
get_latest_versionResolves the latest published version of a Maven Central artifact (any groupId:artifactId — Java, Kotlin, or Scala library). Call this first when you only know the artifact but not the version: the version it returns feeds into every other tool here that takes a concrete version. By default it returns the latest release, sorted by Maven version order and skipping pre-releases; set `includePreReleases` to true to get the newest version of any kind (milestone, RC, beta...), e.g. when a class or method you are looking for is missing from the latest release. Works against the live Maven Central catalog — no local install, build tool, or repository checkout required.
get_source_fileReads one source file from a Maven Central library's sources jar (the `-sources.jar` artifact). Pass the `link` value returned by list_source_files. Use this whenever you need the exact source text of a JVM library — tracing behavior into a dependency, confirming a public API's implementation, finding a definition, or comparing two library versions. Strongly preferred over locating the jar in a local build cache and unzipping it: it works for any Maven Central artifact, no local checkout or build needed.
list_javadoc_symbolsEnumerates the public API a library documents — classes, interfaces, traits, objects, enums, and annotations — for a Maven Central artifact version. Each entry includes the fully-qualified class name (`fqn`) and a `link` that can be passed to get_javadoc_symbol to read the rendered API documentation. Use this to answer 'which classes/types does library X have?' or 'find classes related to <topic>' — it is the fastest way to list the API by name without reading code. Prefer this over list_source_files whenever you only need class/type names. Pass `filter` (e.g. a class name) to get only the matching entries: large libraries list hundreds of symbols, so filtering saves a lot of context when you are looking for one type. Only if this returns NotFoundError because no javadoc jar was published, fall back to list_source_files. Works against the live Maven Central catalog with no local install, build, or checkout required.
list_source_filesLists the raw source files (`.java`, `.kt`, and `.scala`) in a Maven Central artifact version's `-sources.jar`. Each returned path can be passed to get_source_file to read the actual source code. Use this only when you need the implementation — for example, to trace behavior or see how something is wired. To discover which classes exist, or to find classes by topic or name, use list_javadoc_symbols instead; do not use this tool just to enumerate classes. Works against the live Maven Central catalog with no local install, build, or checkout required.
search_artifactsFinds Maven coordinates from part of a library name: searches the javadocs.dev index of Maven Central artifacts for groupId:artifactId values containing every word of the query (case-insensitive). Use this when you know part of a library name (e.g. "jackson", "zio-http", "netty-codec") and need the exact groupId:artifactId coordinates to feed into the other tools. Query with name fragments only — versions are not part of the match. The same artifactId can be published under several groupIds (e.g. jackson-databind: com.fasterxml.jackson.core for 2.x, tools.jackson.core for 3.x), so check each candidate with get_latest_version. To find the library that contains a class, use symbol_to_artifact instead.
symbol_to_artifactFinds which Maven artifact contains a given Java/Kotlin/Scala class: resolves a class name, nested type (e.g. Outer.Builder), fully-qualified type, or package name to the Maven Central artifacts (groupId, artifactId) that publish it. Exact case is preferred; a case-insensitive match is tried if that finds nothing. Several artifacts can contain the same simple name (e.g. a Java and a Scala library): check each result rather than assuming the first. Use this when you have a symbol from a stack trace, an import line, or an error message and you need to know which library to look in. From there, chain into get_latest_version, then list_source_files / list_javadoc_symbols to read the code or docs.