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 d-o-hub/github-template-ai-agents --skill pwa-offline-syncgit clone --depth 1 https://github.com/d-o-hub/github-template-ai-agentsWrote 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/d-o-hub/github-template-ai-agents/pwa-offline-sync)<a href="https://agentmods.dev/skills/d-o-hub/github-template-ai-agents/pwa-offline-sync"><img src="https://agentmods.dev/badge/skills/d-o-hub/github-template-ai-agents/pwa-offline-sync/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/d-o-hub/github-template-ai-agents/pwa-offline-sync"><img src="https://agentmods.dev/badge/skills/d-o-hub/github-template-ai-agents/pwa-offline-sync.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 | $0.00063 | $0.00626 |
| Opus 5 | $0.00032 | $0.00313 |
| Sonnet 5 | $0.00013 | $0.00125 |
| Haiku 4.5 | $0.00006 | $0.00063 |
Grade A, and why
pwa-offline-sync 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 8d 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 — 65 lines — stays where its author put it; the contents beside it link to each section on GitHub.
PWA Offline Sync
Purpose: design, implement, and validate offline/PWA behavior (service worker, caches, IndexedDB, sync queue).
When to Use
- Editing service worker, cache strategies, or sync orchestration.
- Touching IndexedDB schema, permission caching, or zombie detection.
- Investigating offline bugs or data conflicts.
Workflow
- Assess entity rules -- confirm table of offline-first entities + conflict strategy.
- Plan caches -- map static/assets/data to Cache Storage policies (cache-first vs stale-while-revalidate vs network-first).
- IndexedDB schema -- define stores for progress, annotations, sync queue, permission cache; version migrations carefully.
- Service worker -- implement install/activate/fetch with trace logging, offline fallback page, and error handling.
- Sync manager -- queue writes locally, dedupe via mutation IDs, replay when online, implement exponential backoff + zombie detection.
- Testing -- simulate offline/online in E2E tests; unit-test queue reducers; verify revoked access is blocked after reconnect.
Checklist
- Cache + DB version numbers bumped intentionally (no silent clears).
- Headers sent even when offline data queued.
- Zombie detection notifies user + stops further reads upon revocation.
- Service worker cleans up old caches.
- Memory-safe listeners (remove event handlers when replaced).
See Also
lifecycle-management— Resource cleanup and error handlingcss-render-performance— CSS render performance optimization
Rationalizations
| Rationalization | Reality |
|---|---|
| "Cache-first is always the best strategy" | Different data requires different strategies; stale-while-revalidate or network-first may be more appropriate. |
| "Sync queue is overkill for our simple app" | Even simple apps need conflict resolution when offline writes collide with server state. |
| "Zombie detection is too complex to implement" | Without it, revoked users can continue reading cached data indefinitely. |
What ships with it
3 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.
- 8d ago First seen · 65 lines · 63 tokens per session scan A 14ea25ba13b7
pwa-offline-sync is a skill published in the GitHub repository d-o-hub/github-template-ai-agents (2 stars, last pushed yesterday), licensed MIT. It adds 63 tokens to every session and 626 once invoked, about $0.0003 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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