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.
npx skills add dentiny/kon --skill understand-codebasegit clone --depth 1 https://github.com/dentiny/konWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/dentiny/kon/understand-codebase)<a href="https://agentmods.dev/skills/dentiny/kon/understand-codebase"><img src="https://agentmods.dev/badge/skills/dentiny/kon/understand-codebase/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/dentiny/kon/understand-codebase"><img src="https://agentmods.dev/badge/skills/dentiny/kon/understand-codebase.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00042 | $0.01313 |
| Opus 5.5 | $0.00017 | $0.00525 |
| Sonnet 5.5 | $0.00008 | $0.00263 |
| Haiku 4.5 | $0.00004 | $0.00131 |
Grade A, and why
understand-codebase 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 1mo ago.
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.
How it starts
The opening of the file, as written. The whole thing — 125 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Understand Codebase
Consumers: /kon:understand-codebase
Core principles (always): follow skills/core-principles — teach from what the repo actually contains; simplest path through the concepts.
Turn a repository into study materials: key concepts, architecture, flashcards, and a quiz.
Deliverables (after build step)
| Output | Contents |
|---|---|
understand-guide.html |
Primary — interactive guide: click a term, glossary heading, or mermaid node → detail side panel; mermaid + vscode:// / cursor:// source links |
understand-study.html |
Flashcards + quiz with snippets + clickable source links |
understand-guide.pdf |
Optional print export when pandoc + LaTeX are installed |
All files live under sessions/<session-id>/. Orchestrator runs build_understand_codebase.py after Jun finishes.
Pipeline
- 🎸 Azusa (explore) — read-only codebase map → hook saves
understand-explore.md - 📚 Jun (author) — reads explore artifact, writes
understand-guide.md+understand-study.json - Orchestrator —
python3 $KON_ROOT/scripts/build_understand_codebase.py --id "$SID"
Azusa — explore mode
Read agents/Azusa.md. Read-only — no Write/Edit on application source.
Pass SESSION_DIR, EXPLORE_FILE: understand-explore.md.
Required sections (hook persists full output)
## Loaded memory entries
…
## Scope
<what was explored; optional user focus from command>
## Code map
| Area | Key paths | One-line role |
|------|-----------|---------------|
## Concepts spotted (raw)
For each term you see in code/docs — name, where found (`path:line`), rough meaning from evidence:
### <Term>
- **Seen in**: `path:line`, …
- **Notes**: …
## Architecture notes (raw)
- **Deployment shape**: single-node / distributed / hybrid — evidence
- **Major components**: …
- **Data flow**: …
- **External deps**: …
## Implementation anchors
Concrete `path:line` pairs worth flashcard/quiz treatment later.
## Gaps
What could not be determined from the repo alone.
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.
- 1mo ago First seen · 125 lines · 42 tokens per session scan A 623035ce84ea
understand-codebase is a skill published in the GitHub repository dentiny/kon (3 stars, last pushed 3mo ago), licensed MIT. It adds 42 tokens to every session and 1,313 once invoked, about $0.0002 per session on Opus 5.5. 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.
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