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 rules/duckduckgo/apple-browsers/testinggit clone --depth 1 https://github.com/duckduckgo/apple-browsersWhat 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 | $0.00000 | $0.12248 |
| Opus 5 | $0.00000 | $0.06124 |
| Sonnet 5 | $0.00000 | $0.02450 |
| Haiku 4.5 | $0.00000 | $0.01225 |
Grade B, and why
testing scanned grade B with 2 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 yesterday.
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.
Asks for rootmediumPrivilege escalation
A mod that escalates privileges can change anything on the machine, not only the project.
sudo cp com.apple.system.logging.plist /Library/Preferences/Logging/com.apple.system.logging.plist Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
let retrievedBookmark = bookmarkStore.fetch(by: bookmark.id) How it starts
The opening of the file, as written. The whole thing — 1,681 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Testing Guidelines & Best Practices
This guide covers testing practices and patterns for the DuckDuckGo browser on iOS and macOS platforms.
🚨 MANDATORY: Testing Execution Rules
NEVER Run Tests Without Permission
NEVER execute any test commands without EXPLICIT user permission or unles user explicitly asked to in their prompt.
Required Testing Workflow:
- Write or modify test code as requested
- if user did not ask to run tests in their prompt, STOP before running any test commands:
swift testnpm testxcodebuild testfastlane test- Any other test execution commands
- ASK the user: "Should I run the tests?"
- WAIT for explicit permission (e.g., "yes", "run tests", "test it")
- Only then execute test commands
This rule applies to ALL test execution - unit tests, integration tests, UI tests, performance tests, etc.
Future Improvements
This guide is a living document. Consider these areas for future improvements:
- Tab Extensions Testing: Expand patterns for testing complex tab extension interactions and lifecycle management
- WebKit Integration Testing: Add comprehensive patterns for testing WKWebView configurations, user scripts, and content blocking integration
- Privacy Feature Testing: Develop specialized testing approaches for tracker protection, HTTPS upgrade, and content blocking rule validation
- Cross-Platform Testing: Create patterns for testing SharedPackages functionality across iOS and macOS with consistent behavior validation
- Fire Button Integration Testing: Add comprehensive testing patterns for data clearing workflows across all browser components
- Autofill and Credential Testing: Expand testing approaches for AutofillCredentialProvider, password management, and form filling scenarios
- Sync Testing: Develop patterns for testing bookmark sync, conflict resolution, and cross-device data consistency
- AI Chat Integration Testing: Add testing patterns for AI chat functionality, context management, and user interaction flows
- Feature Flag Testing: Expand MockFeatureFlagger usage patterns and integration testing with real feature configurations
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.
- yesterday First seen · 1,681 lines · 0 tokens per session scan B 7f59f51ed055
testing is a cursor rule published in the GitHub repository duckduckgo/apple-browsers (252 stars, last pushed yesterday), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 12,248 tokens. A static security scan graded it B with 2 findings (asks for root, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-01.
Other cursor rules, from other repositories
release-policy
Release, versioning, and signing policy for setmac.
on-load-rule
This guide outlines the critical development principles for this Swift project.
visualization-rule
Creates visual representations of project specifications, tasks, and knowledge.
angular-20
This rule provides comprehensive best practices and coding standards for Angular development, focusing on modern TypeScript, standalone components, signals, and performance optimizations.
dev-standard
Apache Superset development standards and guidelines for Cursor IDE.
cli-error-handling
CLI command error handling patterns.