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 agentmods add skills/sandsower/beislid/walk-the-diffnpx skills add sandsower/beislid --skill walk-the-diffgit clone --depth 1 https://github.com/sandsower/beislidWrote 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/sandsower/beislid/walk-the-diff)<a href="https://agentmods.dev/skills/sandsower/beislid/walk-the-diff"><img src="https://agentmods.dev/badge/skills/sandsower/beislid/walk-the-diff.svg" alt="Measured on agentmods" 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 | $0.00088 | $0.01034 |
| Opus 5 | $0.00044 | $0.00517 |
| Sonnet 5 | $0.00018 | $0.00207 |
| Haiku 4.5 | $0.00009 | $0.00103 |
Grade A, and why
walk-the-diff 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.
How it starts
The opening of the file, as written. The whole thing — 73 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Guided Review
Simulate sitting next to a colleague who wrote the code and having them walk you through the changes. Present diffs in a logical order with context about why each change was made, highlight decision points and scrutiny areas, then pause so the reviewer can ask questions before moving on.
Don't use this for: automated review findings, PR comment posting, fixing feedback, or durable visual reports. Use review, pr-patrol, review-response, or explicit show-me instead.
Global interactive contract
You are the author/presenter, not the reviewer. Explain and defend the change honestly without preemptively rejecting your own code.
The chunk gate is mandatory: never present a new chunk until the reviewer explicitly selects Move on or Flag for follow-up. If the reviewer types free text, treat it as a question/comment, answer it, present the same three options again, and stop.
The three options at every pause are exactly:
Move on— advance to the next chunkI have questions— stay on this chunk; the reviewer will type their question nextFlag for follow-up— note this chunk as needing revisit, then advance
JIT phase protocol
Walk-the-diff phases are authoritative only after their aux files are read. Complete phases in order. At each phase boundary, read the matching file and follow it. If a phase file cannot be read, hard-fail instead of continuing from memory:
🛑 Could not read
skills/walk-the-diff/<phase-file>.md. Walk-the-diff cannot safely execute this phase from memory; reinstall Beislið or restore the file.
- Phase 1:
skills/walk-the-diff/phase-1-context.md - Phase 2:
skills/walk-the-diff/phase-2-tour-plan.md - Phase 3:
skills/walk-the-diff/phase-3-present.md - Phase 4:
skills/walk-the-diff/phase-4-wrap.md
When BEISLID_VERBOSE=1, print one aux load stamp after successfully reading each phase file. Stamp format is ✓ walk-the-diff/<phase-file-stem> v1 loaded for phase-1-context, phase-2-tour-plan, phase-3-present, and phase-4-wrap.
What ships with it
4 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.
- 3d ago First seen · 73 lines · 88 tokens per session scan A 34290c99dce9
walk-the-diff is a skill published in the GitHub repository sandsower/beislid (10 stars, last pushed 4d ago), licensed MIT. It adds 88 tokens to every session and 1,034 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 2026-08-31.
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