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 RevenueCat/play-billing-skills --skill pbl-v8-to-v9-migrationgit clone --depth 1 https://github.com/RevenueCat/play-billing-skillsWrote 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/revenuecat/play-billing-skills/pbl-v8-to-v9-migration)<a href="https://agentmods.dev/skills/revenuecat/play-billing-skills/pbl-v8-to-v9-migration"><img src="https://agentmods.dev/badge/skills/revenuecat/play-billing-skills/pbl-v8-to-v9-migration/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/revenuecat/play-billing-skills/pbl-v8-to-v9-migration"><img src="https://agentmods.dev/badge/skills/revenuecat/play-billing-skills/pbl-v8-to-v9-migration.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 | $0.00084 | $0.02381 |
| Opus 5 | $0.00042 | $0.01190 |
| Sonnet 5 | $0.00017 | $0.00476 |
| Haiku 4.5 | $0.00008 | $0.00238 |
Grade A, and why
pbl-v8-to-v9-migration 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 13d 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 — 163 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Phase 0: Intent
Announce to the user: "I will migrate this project from PBL 8 to PBL 9."
State the key fact up front so the user calibrates effort correctly: PBL 9.0.0 (released 2026-05-19) removed no APIs. PBL 8.0.0 was the breaking release that deleted the Sku* family, queryPurchaseHistoryAsync, and the parameterless enablePendingPurchases(). PBL 9 builds on that surface with one target SDK bump, two compatibility adjustments, and one optional new feature. RevenueCat characterizes it as a single sprint of work for a v8 app.
If the project still references SkuDetails, querySkuDetailsAsync, SkuType, or the parameterless enablePendingPurchases(), the real baseline is pre-v8. Stop and route the user to pbl-v7-to-v9-migration, which does the v8 work first.
Phase 1: Discovery
Gather the facts before changing anything.
- Locate the dependency. Open
build.gradle,build.gradle.kts, orlibs.versions.tomland findcom.android.billingclient:billingorbilling-ktx. Confirm the version reads8.x.x. If it reads7.xor lower, switch to the pbl-v7-to-v9-migration skill. - Check androidx.core. Find the
androidx.core:core/core-ktxversion. v9's error reclassification requires androidx.core 1.9 or later. Record the current value. - Check compile and target SDK. Read
compileSdkandtargetSdk. v9 targets API 35. Note both values. - Scan for developer provided billing. Grep for
DeveloperProvidedBillingDetails,getLinkUri,enableDeveloperBillingOption, andenableBillingProgram. These are the External Payments APIs from PBL 8.3. If any hit, the nullablegetLinkUri()change in Phase 3 applies. If none hit, you can skip that step. - Scan error handling. Grep for
BillingResponseCode.ERRORandBillingResponseCode.BILLING_UNAVAILABLE. Note every place that branches on a genericERRORfor an unavailable store, because v9 reclassifies the blocked store case. - Note in app messaging usage. Grep for
showInAppMessagesandInAppMessageParams. If present, the optional price increase messaging step applies.
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.
- 13d ago First seen · 163 lines · 84 tokens per session scan A e494f921f4d6
pbl-v8-to-v9-migration is a skill published in the GitHub repository RevenueCat/play-billing-skills (53 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 84 tokens to every session and 2,381 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 2026-08-30.
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