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 afaraha8403/balakit --skill subsystem-walkthroughgit clone --depth 1 https://github.com/afaraha8403/balakitWrote 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/afaraha8403/balakit/subsystem-walkthrough)<a href="https://agentmods.dev/skills/afaraha8403/balakit/subsystem-walkthrough"><img src="https://agentmods.dev/badge/skills/afaraha8403/balakit/subsystem-walkthrough/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/afaraha8403/balakit/subsystem-walkthrough"><img src="https://agentmods.dev/badge/skills/afaraha8403/balakit/subsystem-walkthrough.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 | $0.00076 | $0.00602 |
| Opus 5 | $0.00038 | $0.00301 |
| Sonnet 5 | $0.00015 | $0.00120 |
| Haiku 4.5 | $0.00008 | $0.00060 |
Grade A, and why
subsystem-walkthrough 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.
What it actually says
Subsystem walkthrough
Leading words: mental model, one explainer, parallel slices, inherit host model.
Answer "how does X work?" at the level of a senior engineer onboarding onto the subsystem. Not annotated source.
Copy these steps into the todo list verbatim. Skip with skip: <reason>.
- Assess complexity. Simple → one explainer. Complex → 2–4 read-only explorers, then one synthesizer. Write
Complexity: simpleorComplexity: complex (N slices)as the first line of the output. - Explore or explain (see below). Inherit the host model. Do not hardcode a slug.
- Present the explainer output with light edits only. Keep the Complexity line.
When in doubt, take the simple path.
Simple
One read-only subagent explores and explains in a single pass. Fill references/explainer-prompt.md without explorer findings.
Complex
Decompose into 2–4 distinct slices. Spawn explorers in one message, each with references/explorer-prompt.md. Then one synthesizer with the explainer template and every explorer's findings filled in. If the host cannot spawn subagents, run the slices sequentially yourself.
Output
First line: Complexity: simple or Complexity: complex (N slices).
Then: Overview / Key Concepts / How It Works / Where Things Live / Placement / Gotchas. Drop a section that does not apply. Placement is where new code for this subsystem should live (package, file, layer) — one short paragraph, not a second architecture essay.
Reply contract
The Complexity line, then the explanation. Do not rewrite it into a different structure after the explainer returns.
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- yesterday First seen · 65 lines · 76 tokens per session scan A 88223ca3cea6
subsystem-walkthrough is a skill published in the GitHub repository afaraha8403/balakit (1 stars, last pushed 2d ago), licensed MIT. It adds 76 tokens to every session and 602 once invoked, about $0.0004 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 2026-09-11.
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