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 instructions/expensify/app/claude-mdgit clone --depth 1 https://github.com/Expensify/AppWhat 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 | $0.01354 | $0.01354 |
| Opus 5 | $0.00677 | $0.00677 |
| Sonnet 5 | $0.00271 | $0.00271 |
| Haiku 4.5 | $0.00135 | $0.00135 |
Grade A, and why
App CLAUDE.md 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 today.
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 — 107 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Expensify App
HybridApp Architecture
- The mobile application is built from the Mobile-Expensify submodule, not directly from the App repository.
- NewDot refers to the New Expensify App, OldDot or Expensify Classic refers to our Old expensify app and website
Key Integration Points
- App (NewDot) and Mobile-Expensify (OldDot) are combined into a single mobile application
- The HybridApp module (
@expensify/react-native-hybrid-app) manages transitions between OldDot and NewDot - Build process merges
.envfiles from both repositories - Mobile-Expensify environment variables supersede App variables
- Mobile builds must be initiated from the Mobile-Expensify directory
Build Modes
- Standalone: Pure NewDot application (web)
- HybridApp: Combined OldDot + NewDot (mobile apps)
- Controlled via
STANDALONE_NEW_DOTenvironment variable
Navigation & Routing
Key Navigators
- AuthScreens: Authenticated app screens
- PublicScreens: Login and onboarding screens
- RHP (Right Hand Pane): Contextual panels — settings and details
- Central Pane: Main content area
- LHN (Left Hand Navigation): Report list and navigation
State Management
Onyx (react-native-onyx) is our custom offline-first key-value store; keys are defined in src/ONYXKEYS.ts.
Reading Onyx data (useOnyx vs Onyx.connectWithoutView)
Prefer pure functions taking data as params over direct Onyx reads — callers read and pass data in. When a read is needed, use useOnyx (@hooks/useOnyx) by default; reach for Onyx.connectWithoutView only for non-render logic (actions/libraries) that genuinely can't use useOnyx. Don't copy-paste Onyx.connectWithoutView usages — justify each with a comment. Using it in components for perf needs @frontend-performance Slack approval linked in PR description. See Onyx Data Management.
Related Repositories
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.
- today Changed · +8 tokens per session a9a936d0571d
- 2d ago First seen · 107 lines · 1,346 tokens per session scan A ae9f3816d5aa
App CLAUDE.md is an instructions file published in the GitHub repository Expensify/App (5,017 stars, last pushed today), licensed MIT. It adds 1,354 tokens to every session, about $0.0068 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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