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/nylo-core/claude-code/flutter-signingnpx skills add nylo-core/claude-code --skill flutter-signinggit clone --depth 1 https://github.com/nylo-core/claude-codeWhat 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 | $0.00046 | $0.03792 |
| Opus 5 | $0.00023 | $0.01896 |
| Sonnet 5 | $0.00009 | $0.00758 |
| Haiku 4.5 | $0.00005 | $0.00379 |
Grade A, and why
flutter-signing 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 2d 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 — 464 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Flutter Code Signing
Overview
Code signing is required to distribute apps on both iOS and Android. iOS uses certificates and provisioning profiles managed through Apple Developer Program. Android uses Java keystores containing a private key. Both must be properly configured before building release versions.
When to Use
- User needs to build a release version for the first time
- User sees signing-related build errors
- User is setting up CI/CD and needs to configure signing
- User is preparing to submit to App Store or Google Play
- User needs to create or manage signing certificates/keystores
- NOT for debug builds (Flutter handles debug signing automatically)
Quick Reference
| Platform | Signing Mechanism | Key Files | Where Configured |
|---|---|---|---|
| iOS (auto) | Xcode Automatic Signing | Apple Developer account | Xcode project settings |
| iOS (manual) | Certificate + Provisioning Profile | .cer, .p12, .mobileprovision |
Xcode project settings |
| Android | Java Keystore | .jks or .keystore file |
key.properties + build.gradle |
Part 1: iOS Code Signing
Prerequisites
- Apple Developer Program membership ($99/year)
- Xcode installed on macOS
- Apple ID added to Xcode (Xcode → Settings → Accounts)
Automatic Signing (Recommended for Development)
Automatic signing lets Xcode manage certificates and provisioning profiles.
Setup in Xcode:
- Open
ios/Runner.xcworkspacein Xcode - Select the Runner project in the navigator
- Select the Runner target
- Go to Signing & Capabilities tab
- Check Automatically manage signing
- Select your Team from the dropdown
Xcode will automatically:
- Create a signing certificate if needed
- Create and update provisioning profiles
- Handle capability entitlements
In project.pbxproj, automatic signing looks like:
CODE_SIGN_STYLE = Automatic;
DEVELOPMENT_TEAM = YOUR_TEAM_ID;
Manual Signing (Required for CI/CD and Distribution)
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.
- 2d ago First seen · 464 lines · 46 tokens per session scan A 405790bb6f54
flutter-signing is a skill published in the GitHub repository nylo-core/claude-code (4 stars, last pushed 4mo ago), licensed MIT. It adds 46 tokens to every session and 3,792 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 2026-08-31.
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