harb/kraiken-lib/AGENTS.md

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# Kraiken Library - Agent Guide

Shared TypeScript helpers used by the landing app, txnBot, and other services to talk to KRAIKEN contracts and the Ponder GraphQL API.

## Responsibilities
- Provide type-safe contract interaction helpers (encoding inputs, parsing results).
- Supply Ponder GraphQL query helpers and generated types for protocol stats and staking positions.
- Centralise staking math (tax calculations, snatch selection, share conversions) for reuse across clients.

## Key Modules
- `src/staking.ts` - Harberger staking helpers for delinquency checks and snatch math.
- `src/snatch.ts` - Snatch selection engine and supporting types.
- `src/ids.ts` - Position ID encoding helpers.
- `src/subgraph.ts` - Byte utilities shared between the GraphQL layer and clients.
- `src/abis.ts` - Contract ABIs imported directly from `onchain/out/` forge artifacts. Single source of truth for all ABI consumers.
- `src/taxRates.ts` - Generated from `onchain/src/Stake.sol` by `scripts/sync-tax-rates.mjs`; never edit by hand.
- `src/version.ts` - Version validation system tracking `KRAIKEN_LIB_VERSION` and `COMPATIBLE_CONTRACT_VERSIONS` for runtime dependency checking.

## GraphQL Code Generation
- Schema source points to the Ponder GraphQL endpoint for the active environment.
- Scalar mappings: `BigInt` -> `string`, `BigDecimal` -> `string`, `Bytes` -> `string`, `Int8` -> `number`.
- Always import the generated DocumentNodes; avoid `any` casts to keep inference intact.

## Package Scripts
- `npm install --legacy-peer-deps`
- `npm run compile` - Regenerate GraphQL types.
- `npm run watch` - Continuously regenerate on schema changes.
- `npm test` - Execute Jest suite for helper coverage.

## Integration Notes
- Landing app consumes `kraiken-lib/abis`, `kraiken-lib/staking`, and `kraiken-lib/subgraph` for ABI resolution and ID conversion.
- txnBot relies on `kraiken-lib/staking` and `kraiken-lib/ids` to evaluate profitability and tax windows.
- Ponder imports `kraiken-lib/abis` for indexing, and `kraiken-lib/version` for cross-service version checks.
- When the Ponder schema changes, rerun `npm run compile` and commit regenerated types to prevent drift.

## Import Guidance
- The legacy `helpers.ts` barrel has been removed. Always import from the narrow subpaths (e.g. `kraiken-lib/abis`, `kraiken-lib/staking`, `kraiken-lib/snatch`, `kraiken-lib/subgraph`).
- Avoid importing `kraiken-lib` directly; the root module no longer re-exports the helper surface and exists only to raise build-time errors for bundle imports.

## ES Module Architecture
- **Module Type**: This package is built as ES modules (`"type": "module"` in package.json). All consumers must support ES modules.
- **Import Extensions**: All relative imports in TypeScript source files MUST include `.js` extensions (e.g., `from "./staking.js"`). This is required for ES module resolution even though the source files are `.ts`.
- **JSON Imports**: JSON files (like ABI artifacts) must use import assertions: `import Foo from './path.json' assert { type: 'json' }`.
- **TypeScript Config**: `tsconfig.json` must specify:
  - `"module": "esnext"` - Generate ES module syntax
  - `"moduleResolution": "node"` - Enable proper module resolution
  - `"rootDir": "./src"` - Ensure flat output structure in `dist/`
- **Build Output**: Running `npx tsc` produces ES module `.js` files in `dist/` that can be consumed by both browser (Vite) and Node.js (≥14 with `"type": "module"`).
- **Container Mount**: Docker services bind-mount `dist/` read-only from the host. Run `./scripts/build-kraiken-lib.sh` before `docker-compose up` or keep `scripts/watch-kraiken-lib.sh` running to rebuild automatically.

## Quality Guidelines
- Keep helpers pure and side-effect free; they should accept explicit dependencies.
- Prefer narrow exports so downstream consumers can tree-shake bundles.
- Extend typings instead of loosening them; reject `any` as a quick fix.