# Ekx Alchemy

> Alchemy as RPC provider and smart-wallet/account-abstraction platform — API keys per network, gas manager policies for sponsored transactions, the Wallet APIs, NFT and Token APIs, and RPC rate-limit handling. Use when configuring RPC endpoints for any chain, setting up gasless transactions, debugging RPC 429s or eth_getLogs range errors, or working with @alchemy/wallet-apis.

- Skill: `ekinoxis-evm/ekx-alchemy` (Agent Skill)
- Install (CLI): `npx skillmds@latest add ekinoxis-evm/ekx-alchemy`
- Raw SKILL.md: https://api.skillmd.com/api/skills/ekinoxis-evm/ekx-alchemy/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Integrations & APIs
- Author: Ekinoxis-evm (https://skillmd.com/u/ekinoxis-evm)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/ekinoxis-evm/ekx-alchemy

---


# Alchemy

Our RPC provider of record, and — in one lending dApp only — the account-abstraction stack.

Dashboard: https://dashboard.alchemy.com · Docs: https://www.alchemy.com/docs

---

## As an RPC provider (all projects)

```bash
ALCHEMY_API_KEY=                    # SECRET, server-side
NEXT_PUBLIC_ALCHEMY_API_KEY=        # public — MUST be domain-restricted in the dashboard
```

```
https://base-mainnet.g.alchemy.com/v2/${ALCHEMY_API_KEY}
https://base-sepolia.g.alchemy.com/v2/${ALCHEMY_API_KEY}
https://eth-mainnet.g.alchemy.com/v2/${ALCHEMY_API_KEY}
https://eth-sepolia.g.alchemy.com/v2/${ALCHEMY_API_KEY}
https://solana-mainnet.g.alchemy.com/v2/${ALCHEMY_API_KEY}
```

A `NEXT_PUBLIC_` key ships to every browser. That is acceptable **only** with an
allowlist configured in the Alchemy dashboard (Apps → your app → Security → allowed
domains/referrers). Add every Vercel preview domain too, or previews break.

Prefer a server-side proxy route for anything sensitive or expensive — the browser
hits `/api/rpc`, which forwards with the secret key. That also lets you cache.

**Never use `https://mainnet.base.org` in production.** It rate-limits and the
failures are intermittent, which makes them expensive to debug.

---

## Rate limits and CU

Alchemy bills compute units, not requests — `eth_getLogs` over a wide range costs far
more than `eth_blockNumber`. Two rules:

1. **Cap `getLogs` ranges to 10k blocks** and page. Wider returns an error, not a truncated result.
2. **Batch reads with multicall** rather than N single calls. See [`../ekx-viem-wagmi/SKILL.md`](../ekx-viem-wagmi/SKILL.md).

Handle 429 with backoff:

```ts
const transport = http(RPC_URL, { retryCount: 3, retryDelay: 500, batch: true });
```

`batch: true` coalesces concurrent calls into one JSON-RPC batch — often the single
biggest CU reduction available.

---

## Smart wallets / gas sponsorship

One lending dApp uses `@alchemy/wallet-apis` for ERC-4337 smart accounts with sponsored gas,
so LATAM SME borrowers never need to hold ETH.

```bash
NEXT_PUBLIC_ALCHEMY_POLICY_ID=           # gas manager policy
NEXT_PUBLIC_ALCHEMY_POLICY_ID_ETH=
NEXT_PUBLIC_ALCHEMY_POLICY_ID_SEPOLIA=
```

A **gas manager policy** is created in the dashboard and defines who gets sponsored
and how much: allowlisted contract addresses, per-user and global spend caps, expiry.
Configure the caps before going anywhere near mainnet — an open policy is a faucet
for anyone who finds the policy ID, which is public by construction.

Policies are per-chain. A multi-chain app carries one ID per chain for that reason; the wrong ID for
the active chain fails with an unhelpful "policy not found".

Related: `@privy-io/alchemy-migration` exists for this — such a repo
moved from Privy's own smart wallets to Alchemy's. Expect both code paths to exist.

---

## Other Alchemy APIs in use

- **NFT API** (`nft-cdn.alchemy.com`) — token metadata and images without running an indexer. Used for NFT previews.
- **Token API** — balances by owner. Cheaper than looping `balanceOf`.
- **x402** (`x402.alchemy.com`) — pay-per-request HTTP payments; see [`../ekx-x402/SKILL.md`](../ekx-x402/SKILL.md).

---

## Gotchas

1. **Unrestricted public key.** Restrict by domain, always.
2. **`getLogs` > 10k blocks** errors. Page it, or use a subgraph.
3. **Per-chain policy IDs.** Not interchangeable.
4. **CU exhaustion looks like a bug**, not a bill — sudden intermittent read failures near month-end are worth checking against the dashboard.
5. **Free tier is shared per app**, so a busy preview deploy can starve production. Separate apps per environment.