/code-overview

name: "code-overview"
description: >
  Produces a human-readable, progressive-disclosure overview of unfamiliar code or a pull request's changes — why it
  exists (the real problem it solves or goal it serves for the business or a user), and from there what it does, how it
  flows, and where to start — so you can get up to speed before working on or reviewing it. Use when you want to
  understand, get oriented in, make sense of, explain, or get up to speed on a chunk of code, a file, a directory, a
  symbol, or a PR's changes. Writes the overview to a scratch file and changes no code. Does not review code quality or
  raise findings — use code-review for auditing changes or post-code-review-to-pr for posting them. Does not produce
  durable feature or system documentation — use project-documentation. Does not assess architecture or structural risk —
  use architectural-analysis. Does not diagnose bugs or root-cause failures — use investigate. Does not pace a person
  through the code one step at a time in conversation — use code-walkthrough.
arguments: size
argument-hint:
  "[size: small | medium | large | dynamic] [target: file, directory, symbol, or PR reference — defaults to the current branch's
  changes]"
allowed-tools:
  Read, Glob, Grep, Agent, Write, Bash(git *), Bash(gh *), Bash(find *),
  Bash(bash "${CLAUDE_PLUGIN_ROOT}/scripts/han-config-dir.sh")

Project Context

• git installed: !`which git 2>/dev/null || echo "not installed"`
• gh installed: !`which gh 2>/dev/null || echo "not installed"`
• CLAUDE.md: !`find . -maxdepth 1 -name "CLAUDE.md" -type f`
• project-discovery.md: !`find . -maxdepth 3 -name "project-discovery.md" -type f`
• personal config directory: !`bash "${CLAUDE_PLUGIN_ROOT}/scripts/han-config-dir.sh" 2>/dev/null || echo "$HOME/.claude"`
• project .han/config.md: !`cat .han/config.md 2>/dev/null || echo ""`

As your first action, use the Read tool on `.han/config.md` inside the `personal config directory` path above. A read that returns no file is no personal configuration: continue silently. When that file or the `project .han/config.md` probe supplies content, apply it per [config-rule.md](../../references/config-rule.md), which governs precedence between the two files, relative-path resolution, and what to do with a file that reads but cannot be used.

Operating Principles

Read these before doing anything. They constrain every step below.

• **"Why" is the organizing question.** The overview exists to answer one question first: _why does this code exist?_ —

and the answer is the real problem it solves or the goal it accomplishes for the business or a user, never the technical mechanics. Why it exists, why it works the way it does, why it is the current solution to a real need: that is the spine of the whole document. Everything else the overview carries — what it does, how it flows, where it connects, where to start — flows out of the why and exists to give the reader the context to understand it. "What", "how", "where", and "when" are not dropped or diminished; they are framed by and subordinated to the "why" they serve. BECAUSE a reader who knows what code does but not why it exists cannot make sound decisions about it — the why is the load-bearing understanding, and the rest is scaffolding around it. State the why as a solution to a need, and never invent a business rationale the evidence does not support; when the why can only be inferred, mark it as inferred.

• **The skill orchestrates and synthesizes; the agents discover, validate, then refine.** The skill resolves the target,

classifies size, dispatches exploration, and writes the overview. `han-core:codebase-explorer` agents gather the surrounding code and context the synthesis draws on — they do not write the overview. After the draft is written, `han-core:adversarial-validator` re-reads the code to challenge the draft's claims for accuracy, and `han-communication:readability-editor` rewrites the corrected draft against the shared readability standard, preserving every fact; the skill applies the validator's corrections and the editor's rewrite. The skill itself produces the grouping, the charts, the orientation, and the final rewrite.

• **The overview applies the shared readability standard.** As it writes and refines the overview, the skill sources the

standard by invoking `han-communication:readability-guidance` (Step 5) and applies it, holding the default audience frame: a capable reader who did not do this work and lacks the author's context. The standard governs how the overview reads (main point first, descriptive headings, one idea per paragraph, progressive disclosure), never whether a required fact about the code appears. Its dedicated `han-communication:readability-editor` pass (Step 7) replaces the older information-architect / junior-developer readability review; the accuracy validator is a separate pass and stays.

• **Diagram legibility is this skill's job, not the editor's.** The readability rewrite pass is barred from touching

diagram bodies, so nothing but this skill checks whether a chart can be read. Apply the template's diagram rule as you draw each chart: boxes name components and boundaries, and fields, types, and technical annotations go into the prose beneath. BECAUSE the exemption is right for accuracy — an editor free to reword a box could silently change what the chart claims about the code — and the reading load it leaves behind has to land on someone.

• **Read-only, always.** The skill explains; it never edits the target. It writes only its own scratch overview file.

BECAUSE the job is understanding, not modification — this keeps the skill safe to point at unfamiliar code.

• **Accurate to the code, always.** Every claim the overview makes — the why it states (grounded in commit and PR/issue

intent, comments, and what the code visibly does toward a goal), what the code does, each flow step, each named ent