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 thedaviddias/Front-End-Checklist --skill back-forward-cachegit clone --depth 1 https://github.com/thedaviddias/Front-End-ChecklistWrote 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/thedaviddias/front-end-checklist/back-forward-cache)<a href="https://agentmods.dev/skills/thedaviddias/front-end-checklist/back-forward-cache"><img src="https://agentmods.dev/badge/skills/thedaviddias/front-end-checklist/back-forward-cache.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00035 | $0.00446 |
| Opus 5 | $0.00017 | $0.00223 |
| Sonnet 5 | $0.00007 | $0.00089 |
| Haiku 4.5 | $0.00003 | $0.00045 |
Grade A, and why
back-forward-cache 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 9d 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.
The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
What ships with it
1 file 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.
- 9d ago First seen · 47 lines · 35 tokens per session scan A 4d6361da2e7e
back-forward-cache is a skill published in the GitHub repository thedaviddias/Front-End-Checklist (74,068 stars, last pushed 25d ago), with no licence file. It adds 35 tokens to every session and 446 once invoked, about $0.0002 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 2026-08-30.
Other skills, from other repositories
uisandbox
Open a real, built web app in UISandbox — the interactive sandbox in the user's browser, 1:1, with the app's own knobs (brand, colours, fonts, radius, spacing…) — or test one change headlessly, verify it still renders 1:1, get a screenshot and the patch. Use when someone wants to look at their app in a sandbox and…
mobile-viewport-fit
Make full-screen web apps (game boards, tools with fixed header + flexible content + fixed keyboard/footer) fit on mobile without scrolling. Solves the common problem where 100vh includes the browser address bar area on mobile, causing content to overflow below the visible viewport.
design-mode
Activate or deactivate the visual Design Mode overlay on a web page in the browser. Use when the user says 'activate design mode', 'turn on design mode', 'start design mode', 'inject overlay', 'enable element inspection', or 'deactivate design mode', 'turn off design mode', 'remove overlay'.
annotate
Process and apply user annotations from Design Mode. Use when the user says 'apply annotations', 'process my design comments', 'fix those', 'apply my changes', 'do what I noted', 'apply design feedback', or when the auto-read hook detects pending annotations.
inspect-element
Read and return detailed information about selected elements from the Design Mode overlay. Use when the user says 'what did I select', 'inspect element', 'show element details', 'read element', 'what element is that', 'show me element info', or references an element from the overlay.
claude-in-chrome-troubleshooting
Diagnose and fix Claude in Chrome MCP extension connectivity issues. Use when mcpclaude-in-chrome tools fail, return "Browser extension is not connected", or behave erratically.