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 yarlson/yarstack --skill changes-explaingit clone --depth 1 https://github.com/yarlson/yarstackWrote 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/yarlson/yarstack/changes-explain)<a href="https://agentmods.dev/skills/yarlson/yarstack/changes-explain"><img src="https://agentmods.dev/badge/skills/yarlson/yarstack/changes-explain/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/yarlson/yarstack/changes-explain"><img src="https://agentmods.dev/badge/skills/yarlson/yarstack/changes-explain.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 | $0.00048 | $0.00370 |
| Opus 5.5 | $0.00019 | $0.00148 |
| Sonnet 5.5 | $0.00010 | $0.00074 |
| Haiku 4.5 | $0.00005 | $0.00037 |
Grade A, and why
changes-explain 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 3d 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.
What it actually says
Explain Changes
Translate one code comparison into its effects on the system, without inventing intent or exposing sensitive content.
Workflow
- Fix the comparison. For a branch or pull request, compare against the merge base (
git diff <base>...<head>, orgh pr diff), not the current tip of the base branch. For local work, include staged, unstaged, and untracked files. If the scope cannot be isolated, say so and qualify the explanation. - Read the diff, the full changed files, the surrounding code they depend on, the tests, the configuration, and any linked brief that is in scope.
- Group the edits by changed behavior or responsibility, not by file.
- For each group, explain the previous and new behavior, the affected owner or boundary, the data and control flow, the external interactions, and the effects on users, developers, runtime, or operations.
- Describe changed failure handling, compatibility, rollout, CI, verification, and remaining risk where the change alters them.
- Mark what you observed in code, what the documentation or pull request says was intended, and what you infer.
Keep the task read-only. Redact secrets and sensitive diff content. Use code-review for defect findings and rollout-readiness-review for an operational-readiness judgment.
Result
Start with a short summary of the overall change, then explain each group. Omit syntax trivia and empty sections. Finish when every material group is explained and the evidence limits are stated.
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.
- 3d ago Changed · +2 lines 6f7fa73fbea7
- 1mo ago First seen · 22 lines · 48 tokens per session scan A 539b5c9d2ca3
changes-explain is a skill published in the GitHub repository yarlson/yarstack (3 stars, last pushed 2d ago), licensed MIT. It adds 48 tokens to every session and 370 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.
Other skills, from other repositories
fix
Fix a bug grounded in Hunch (past root causes, constraints, blast radius).
work-audit
Evidence-first, read-only audits that always use one gpt-5.6-sol xhigh analyst and return a self-contained fix plan suitable for a lower-capability execution model. Use when the user asks to audit code, a diff, a branch, an artifact, or a runtime flow.
debug-issue
Systematically debug issues using graph-powered code navigation.
systemic-issue-triage
Trigger: new issue, bug report, triage, backlog, issue flood, community report, root cause, dead-end, blocked user. Attack issues by root class, never one-by-one; fixes must shrink the system, not grow it.
issue-root-resolution
Trigger: root audit, atacar la raíz, issue roots, backlog roots, mechanism map, deletion-driven fix, resolver issues de raíz, close outdated issues. Audit and resolve issue clusters by verified root cause.
rdd-defect-workflow
Trigger: RDD, receipt-driven development, review authority, receipt/lineage, correction/recovery, delivery gate/kill switch, bounded review defects. Guide work.