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+CLAUDE.md
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+# AGENTS.md - toolkit
+
+This is the Across Protocol toolkit monorepo — home of the `@across-protocol/app-sdk`, the TypeScript SDK for integrating Across bridging and swaps into dApps.
+
+## How to use docs in this repo
+
+Read docs in this order:
+
+1. This file (`AGENTS.md`) for top-level navigation and module map.
+2. `packages/sdk/README.md` for SDK usage, authentication, and examples.
+3. `apps/example/` for working integration examples (viem + ethers).
+
+## Documentation maintenance
+
+Keep all relevant `AGENTS.md` and `README.md` files updated in the same change whenever SDK APIs, actions, or types change.
+
+- Before writing implementation plans, surface material ambiguities first and resolve them with the user.
+- For each new task, propose 0-3 targeted updates to `AGENTS.md` or `README.md` files (or explicitly state why no updates are needed).
+- When adding new SDK actions, update the action list in this file and the SDK README.
+
+## Quick index
+
+- SDK source: `packages/sdk/src/`
+- SDK entry point: `packages/sdk/src/index.ts`
+- SDK client: `packages/sdk/src/client.ts`
+- SDK actions: `packages/sdk/src/actions/`
+- API layer: `packages/sdk/src/api/`
+- SDK types: `packages/sdk/src/types/`
+- SDK utilities: `packages/sdk/src/utils/`
+- SDK tests: `packages/sdk/test/`
+- Example app (viem): `apps/example/app/viem/`
+- Example app (ethers): `apps/example/app/ethers/`
+- Changesets: `.changeset/`
+
+## SDK actions
+
+The SDK exposes these actions through `AcrossClient`:
+
+**Quotes and routes:**
+- `getSuggestedFees` — Protocol fee suggestions
+- `getAvailableRoutes` — Discover supported routes
+- `getLimits` — Transfer limits
+- `getQuote` — Bridge quote
+- `getSwapQuote` — Swap + bridge quote
+- `getSwapTokens` — Available swap tokens
+- `getSwapChains` — Available swap chains
+
+**Execution:**
+- `executeQuote` — Execute a bridge quote
+- `executeSwapQuote` — Execute a swap + bridge quote
+- `simulateDepositTx` — Simulate deposit transaction
+- `simulateApproveTx` — Simulate token approval
+- `simulateUpdateDepositTx` — Simulate deposit update
+
+**Tracking:**
+- `waitForDepositTx` — Wait for deposit confirmation
+- `waitForFillTx` — Wait for fill on destination chain
+- `getDeposit` — Get deposit by ID
+- `getDepositFromLogs` — Parse deposit from tx logs
+- `getFillByDepositTx` — Find fill for a deposit
+
+**Other:**
+- `signUpdateDeposit` — Sign deposit update message
+
+## Directory tree
+
+```text
+toolkit/
+├── packages/
+│   ├── sdk/                          # @across-protocol/app-sdk
+│   │   ├── src/
+│   │   │   ├── index.ts              # Main export
+│   │   │   ├── client.ts             # AcrossClient class
+│   │   │   ├── actions/              # 18 SDK action implementations
+│   │   │   ├── api/                  # API communication (routes, fees, swap)
+│   │   │   ├── abis/                 # SpokePool ABIs (v3, v3_5)
+│   │   │   ├── constants/            # SDK constants
+│   │   │   ├── errors/               # Error types
+│   │   │   ├── types/                # TypeScript type definitions
+│   │   │   └── utils/                # Utilities (logger, multicall, tenderly, etc.)
+│   │   ├── test/
+│   │   │   ├── unit/                 # Unit tests
+│   │   │   ├── e2e/                  # End-to-end tests
+│   │   │   ├── mocks/               # API mocks and fixtures
+│   │   │   └── common/              # Test setup and helpers
+│   │   ├── vitest.config.ts          # Test configuration
+│   │   └── package.json              # Peer dep: viem@^2.31.2
+│   ├── eslint-config/                # Shared ESLint config
+│   └── typescript-config/            # Shared TypeScript config
+├── apps/
+│   └── example/                      # Next.js demo app
+│       ├── app/viem/                 # viem + wagmi integration example
+│       ├── app/ethers/               # ethers v5 integration example
+│       └── scripts/                  # CLI demo scripts
+├── turbo.json                        # Turborepo config
+├── pnpm-workspace.yaml               # Workspace definition
+├── .changeset/                       # Changeset versioning
+└── package.json                      # pnpm, Node >=18
+```
+
+## Build and test
+
+```bash
+# Build all packages
+pnpm build
+
+# Run all tests
+pnpm test
+
+# Run SDK tests only
+cd packages/sdk && pnpm test
+
+# Lint and type-check
+pnpm lint
+
+# Format
+pnpm format
+
+# Release workflow
+pnpm version-packages    # Changeset version bump
+pnpm release             # Build + publish to npm
+```
+
+## Release process
+
+This repo uses [changesets](https://github.com/changesets/changesets) for versioning:
+
+1. Create a changeset: `pnpm changeset`
+2. Version packages: `pnpm version-packages`
+3. Merge to master — CI publishes automatically via GitHub Actions.
+
+## Key dependencies
+
+- **viem** (peer dependency, ^2.31.2) — Ethereum client library
+- **zod** — Runtime type validation
+- **Vitest** — Test framework
+- **MSW** — API mocking in tests
diff --git a/CLAUDE.md b/CLAUDE.md
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+AGENTS.md
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