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.
NewMaintained
Automatic
◆Coding pack
Last verified 9/25/2026
What it changes
4 of 23 test cases passed with the skill.
Pass-rate lift
—
Tokens
+363%
Agent turns
0%
Response time
-12%
Model gemini-3.6-flashMeasured 9/25/2026v24 of 23 cases passed with skill · 5 comparable
Tokens, turns and time describe resource use, not a dollar price.
Lift withheld: 5 comparable cases; this report requires 8.
See it in action
One of 2 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 2
Prompt
Create an overview for pull request https://github.com/org/repo/pull/405 when the GitHub CLI tool gh is missing from the system.
What was checked, without and with the skill
Checked
Without skill
With skill
Informs the user that the gh tool is required to read named pull requests.
Missed
Passed
Offers code mode on a local target as an alternative.
Missed
Passed
case-08 · gemini-3.6-flash · 9/25/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
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, 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
Walks a person through code changes one step at a time in conversation, starting at the entry point and following the flow that changes, showing a small chunk per step and explaining it in plain language. Defaults to the current branch's changes, and walks the code from the perspective of any context provided instead — a file, directory, symbol, pull request, plan, or ticket. Use when someone wants to be walked through, taught, paced through, or shown around code or a branch step by step, or to