A terminal-based tool for exploring the API, members, and source code of JVM libraries.

Install

mkdir -p .claude/skills/cellar && curl -L -o skill.zip "https://agentskills.codes/api/skills/download/16860" && unzip -o skill.zip -d .claude/skills/cellar && rm skill.zip

Installs to .claude/skills/cellar

Activation

This is the description your AI agent reads to decide when to run this skill — the better it matches your request, the more reliably it fires.

Look up the public API of any JVM dependency (Scala 3, Scala 2, Java) from the terminal. Returns type signatures, members, docstrings, and source code as Markdown.
163 charsno explicit “when” trigger
Intermediate

Key capabilities

  • Look up type signatures for JVM dependencies
  • Search for members within a package or class
  • Fetch source code for published artifacts
  • Query dependency trees for Maven coordinates
  • List symbols in a specified package
  • Search for symbols by name

How it works

The skill executes `scripts/cellar` commands with specified arguments to query JVM dependencies or project codebases.

Inputs & outputs

You give it
Maven coordinate and fully qualified name (FQN)
You get back
Markdown formatted type signatures, members, docstrings, or source code

When to use cellar

  • Looking up library API signatures
  • Searching for class members
  • Fetching source code for dependencies
  • Exploring JVM project dependencies

About this skill

Cellar

Use cellar to look up the API of JVM dependencies instead of guessing or hallucinating signatures. You find the executable in scripts/cellar. e.g.

# Look up a Scala 3 trait
scripts/cellar get-external org.typelevel:cats-core_3:2.10.0 cats.Monad

Translate the examples below to this pattern, calls scripts/cellar instead of cellar.

Project-aware commands (run from project root)

Query the current project's code and all its dependencies. Cellar auto-detects the build tool (Mill, sbt, scala-cli).

scripts/cellar get [--module <name>] <fqn>       # single symbol (signature, members, docs)
scripts/cellar list [--module <name>] <package>  # list symbols in a package or class
scripts/cellar search [--module <name>] <query>  # case-insensitive substring search
  • Mill/sbt projects: --module is required (e.g. --module lib, --module core)
  • scala-cli projects: omit --module
  • --no-cache: skip classpath cache, re-extract from build tool
  • --java-home <path>: override JRE classpath
  • -l, --limit <N>: max results for list/search (default: 50)

External commands (query arbitrary Maven coordinates)

Query any published artifact by explicit coordinate (group:artifact:version):

cellar get-external <coordinate> <fqn>       # single symbol
cellar list-external <coordinate> <package>  # list symbols
cellar search-external <coordinate> <query>  # search by name
cellar get-source <coordinate> <fqn>         # fetch source code
cellar deps <coordinate>                     # dependency tree
  • Coordinates must be explicit: group:artifact_3:version (no :: shorthand)
  • For sbt plugins, use the full Scala and sbt suffix: group:artifact_2.12_1.0:version (e.g. org.scala-native:sbt-scala-native_2.12_1.0:latest)
  • For compiler plugins and other artifacts with full Scala version suffixes, use the full version: group:artifact_3.3.8:version
  • Use latest as the version to resolve the most recent release
  • -r, --repository <url>: extra Maven repository (repeatable)

Workflow

  1. Don't know the package?cellar search / cellar search-external
  2. Know the package, not the type?cellar list / cellar list-external
  3. Know the type?cellar get / cellar get-external
  4. Need the implementation?cellar get-source

Examples

# Look up a Scala 3 trait
cellar get-external org.typelevel:cats-core_3:2.10.0 cats.Monad

# Look up a Java class
cellar get-external org.apache.commons:commons-lang3:3.14.0 org.apache.commons.lang3.StringUtils

# List a package
cellar list-external io.circe:circe-core_3:0.14.6 io.circe

# Search for a method
cellar search-external org.typelevel:cats-core_3:2.10.0 flatMap

# Get source code
cellar get-source org.typelevel:cats-core_3:2.10.0 cats.Monad

# Dependency tree
cellar deps org.typelevel:cats-effect_3:3.5.4

# sbt plugin (use full Scala + sbt suffix)
cellar deps org.scala-native:sbt-scala-native_2.12_1.0:latest

# Project-aware (from a Mill project root)
cellar get --module lib cats.Monad
cellar list --module core cats
cellar search --module lib flatMap

Output

  • stdout: Markdown — ready to consume directly
  • stderr: diagnostics (warnings, truncation notices)
  • Exit 0: success, Exit 1: error

When not to use it

  • When the dependency is not a JVM artifact
  • When the exact Maven coordinate is unknown
  • When the project is not built with Mill, sbt, or scala-cli

Limitations

  • Requires explicit `group:artifact:version` coordinates for external commands
  • Requires `--module` for Mill/sbt projects
  • Does not support `::` shorthand for Maven coordinates

How it compares

This skill directly queries JVM dependencies and project classpaths from the terminal, providing structured output without manual decompilation or external documentation searches.

Compared to similar skills

cellar side by side with the closest alternatives in the catalog.

SkillInstallsUpdatedSafetyDifficulty
cellar (this skill)04moReviewIntermediate
workflow-orchestration-patterns103moNo flagsAdvanced
ark-analysis04moReviewBeginner
coding06moNo flagsAdvanced

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