explore-codebase-cli

A command-line explorer for Java and Kotlin projects that searches files and navigates a map of code relationships.

In plain words
What is it for?
Use it to find code and configuration, trace callers and callees, inspect routes and clients, follow asynchronous message flows, and analyze dependencies.
Why use it?
It helps answer questions about where code is, how components connect, and what a change might affect without scanning the whole project manually.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/humanbean17/jrag/explore-codebase-cli
Any agent
npx skills add HumanBean17/jrag --skill explore-codebase-cli
Clone the repo
git clone --depth 1 https://github.com/HumanBean17/jrag

Made for: Claude Code, Codex.

Per session 129 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,095 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00129 $0.03095
Opus 5 $0.00064 $0.01548
Sonnet 5 $0.00026 $0.00619
Haiku 4.5 $0.00013 $0.00310

Measured yesterday against content hash 6fe3addded09, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

explore-codebase-cli scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/explore-codebase-cli/SKILL.md · 108 lines

How it starts

The opening of the file, as written. The whole thing — 108 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Core Principles

  1. Smallest sufficient tool — both ways. Pick the lightest tool that answers the question. Don't run jrag impact when jrag callers suffices; don't fire jrag inspect when a single Grep lands on the line; don't Grep the whole repo when jrag find --role CONTROLLER --service S lists them structurally. Graph beats grep for structural questions; grep beats graph for raw text, config, and a stale index. Neither is the default — match the tool to the question.
  2. Excerpts over dumps. Read excerpts and relevant sections, not entire files. Summarize findings.
  3. Stop when answered. Don't prefetch unrelated subgraphs or scan unrelated directories.

Tool Inventory

  • jrag CLI — navigate & search: one command per intent — graph navigation (callers, callees, hierarchy, implementations, dependents, impact, flow, http-routes, http-clients, producers, topics, overview), search (locate code or config by meaning, keywords, or natural language), and find/inspect (resolve identifiers; list nodes by role/kind). Drives the same index as the MCP server. Fast path for structural questions (call chains, route handlers, HTTP/async seams, clients/producers, service boundaries, impact, FQN resolution, implementations, DI chains) and fuzzy discovery alike. Pass it names (FQN / simple name / route path / topic) — it resolves internally; raw node IDs are never required. Requires an index; if unindexed every command exits 2 (see jrag surface).
  • File-system: Grep (content/regex), Glob (name/path patterns), Read (offset/limit). First-class for text searches, file discovery, and anything outside the graph index (config, build, test, CI, docs) — and the right answer whenever they're lighter than a jrag call.
  • Other: Bash (read-only: git log, git blame, ls, find), WebSearch/WebFetch.

CLI surface only — don't also drive the MCP tools (search/find/describe/neighbors/resolve) in the same session; the two vocabularies conflict.

Read the full file on GitHub · 108 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 108 lines · 129 tokens per session scan A 6fe3addded09

Subscribe to this mod's changes

explore-codebase-cli is a skill published in the GitHub repository HumanBean17/jrag (9 stars, last pushed 6d ago), licensed MIT. It adds 129 tokens to every session and 3,095 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other skills, from other repositories

test

Run /test to write a test suite for code you just built or changed, after implementing a feature, route, or fix. Targets uncommitted changes automatically, reads test preferences.json for your framework (asks and saves it if absent), and picks the right strategy per file: happy path, edge cases, error states…

jsmastery-pro/skills · 69 tokens

develop

Run /develop to build a feature, UI or backend, from an approved design, a page, component, API, service, or data slice. If something load bearing is undecided and no spec records it, it stops and routes you to /architect; otherwise it reads the spec plus AGENTS.md, builds, and advances the scope.

jsmastery-pro/skills · 71 tokens

sync

Run /sync as the last step after a change is complete, around merge, to keep durable knowledge current. Updates root and nested AGENTS.md, reconciles the scope from repo evidence, and flags specs the change made stale. Surgical edits only: it adds lines, and rewrites single lines it owns. Never a whole section, never…

jsmastery-pro/skills · 73 tokens

document

Run /document pr | changelog | release-note | postmortem (or let it ask) to write the human facing prose about a change. Drafts from the real commits and diff, writing to the right place. Does not write code, tests, or specs.

jsmastery-pro/skills · 65 tokens

debug

Run /debug to find and fix a bug's root cause: a test failing for an unclear reason, /check verify finding a failure, or behavior being wrong. Runs a reproduce, localize, hypothesize, test, fix, verify loop, makes the minimal fix, and hands a regression test to /test. No features, no extra refactors.

jsmastery-pro/skills · 74 tokens

check

Confirm a change before merge. /check verify drives the real app to prove behavior against the spec (every acceptance criterion met, every surface built). /check review runs a senior code review on a fresh model, one that did not write the code. Verify after /develop, review before a PR. Writes to docs/reviews/, never…

jsmastery-pro/skills · 74 tokens