feat(vibenet): cover Cobalt 200ms blocks, migrate to current fork API…

README.md

@@ -31,7 +31,7 @@ Consolidated skills that cover the most common use cases. Each uses progressive
 | ----- | ------- | ----------- |
 | [build-on-base](./skills/build-on-base/SKILL.md) | `npx skills add base/skills --skill build-on-base` | Complete Base development playbook: network, contracts, wallet auth, payments, attribution, and migrations. Consolidates all individual skills into one. |
 | [base-mcp](./skills/base-mcp/SKILL.md) | `npx skills add base/skills --skill base-mcp` | Base MCP server — gives your AI assistant a wallet via mcp.base.org. Sending, swapping, signing, batched calls, balances, and partner plugins for lending, swaps, and more. |
-| [vibenet](./skills/vibenet/SKILL.md) | `npx skills add base/skills --skill vibenet` | Build on [vibenet](https://chain.base.org/vibenet), the Base Vibes devnet for native account abstraction (EIP-8130) with viem: smart accounts, batched calls, session keys and policies, and ERC-8168 payer gas sponsorship. |
+| [vibenet](./skills/vibenet/SKILL.md) | `npx skills add base/skills --skill vibenet` | Build on [vibenet](https://chain.base.org/vibenet), the Base Vibes devnet for native account abstraction (EIP-8130) and Cobalt 200ms native blocks, with viem: smart accounts, batched calls, session keys and policies, ERC-8168 payer gas sponsorship, and millisecond block timestamps. |
 
 ## Installation
 
@@ -75,6 +75,10 @@ Create an EIP-8130 smart account on vibenet and fund it from the faucet
 Deploy a smart account on vibenet with sponsored gas, so the user needs no ETH
 ```
 
+```text
+Send a transaction on vibenet and show me which 200ms block it landed in
+```
+
 ## Contributing
 
 See [CONTRIBUTING.md](CONTRIBUTING.md) for guidelines.

skills/vibenet/SKILL.md

@@ -1,14 +1,17 @@
 ---
 name: vibenet
 description: >-
-  Build on vibenet — Base's devnet for native account abstraction (EIP-8130)
-  and payer gas sponsorship (ERC-8168) using viem's eip8130 module. Use
+  Build on vibenet — Base's devnet for native account abstraction (EIP-8130),
+  payer gas sponsorship (ERC-8168), and Cobalt 200ms native blocks. Use
   whenever the user mentions vibenet, EIP-8130, ERC-8168, 8130 accounts, native
-  account abstraction, session keys, actors, policies, payers, or gas
-  sponsorship on Base — or is writing code that creates or operates 8130 smart
-  accounts, authorizes session-key actors, sends batched calls, sponsors gas
-  with a payer, or wires a frontend/script against the vibenet devnet or Base
-  Sepolia.
+  account abstraction, session keys, actors, policies, payers, gas sponsorship
+  on Base, 200ms blocks, Cobalt, BaseTime, timestampMs / blockTimestampMs,
+  sub-second or millisecond block timestamps, migrating from Flashblocks, or
+  newHeads / WebSocket streaming on vibenet — or is writing code that creates
+  or operates 8130 smart accounts, authorizes session-key actors, sends batched
+  calls, sponsors gas with a payer, queries or streams vibenet blocks, times a
+  transaction's inclusion, or wires a frontend/script against the vibenet
+  devnet or Base Sepolia.
 ---
 
 # Vibenet
@@ -18,19 +21,25 @@ abstraction in the protocol itself. Accounts are portable across EVM chains,
 support multiple signer types (secp256k1, P-256, WebAuthn), key rotation
 without changing address, scoped session-key actors, on-chain policies, and
 native **ERC-8168** gas sponsorship. The tooling lives in viem's `eip8130`
-module (fork branch — not yet in npm `viem`).
+module (fork branch — not yet in npm `viem`). Vibenet is also the first Base
+network running **Cobalt 200ms native blocks** (five canonical blocks per
+second, with a millisecond `timestampMs` on every block) — that part needs no
+fork, stock `viem` works. See
+[references/200ms-blocks.md](references/200ms-blocks.md).
 
 ## Network
 
 | Endpoint | Value |
 |----------|-------|
 | Chain ID | `84538453` |
 | Public execution RPC | `https://rpc.vibes.base.org` — 8130-capable (`AA_TX_TYPE` / `0x79`), serves `access-control-allow-origin: *` |
+| WebSocket RPC | `wss://rpc.vibes.base.org/ws` — `newHeads`, `logs`, `transactionReceipts` subscriptions (the `/ws` path is required) |
+| Block time | **200ms** (Cobalt); blocks carry `timestampMs`, BaseTime predeploy at `0x4200000000000000000000000000000000000030` |
 | Browser RPC proxy | `https://api.vibes.base.org/api/vibenet/account/rpc` — passes through all `eth_*`, including `0x79` broadcasts and receipt polling |
 | Hosted payer (ERC-8168) | `https://api.vibes.base.org/api/vibenet/account/payer` |
 | Faucet | `POST https://api.vibes.base.org/api/vibenet/faucet/drip` with `{ "address": "0x…" }` |
 | Faucet status | `GET https://api.vibes.base.org/api/vibenet/faucet/status` — drip size, cooldowns, USDV/NFV token addresses |
-| Chain health | `GET https://api.vibes.base.org/api/vibenet/chain-health` — `{ healthy, head, headAgeSecs, … }` |
+| Chain health | `GET https://api.vibes.base.org/api/vibenet/chain-health` — key off `healthy` + `headAgeSecs`; `stuckSecs` is not actionable on its own (seen at 19000 on a healthy chain) |
 | Landing page / explorer | `https://chain.base.org/vibenet`, `https://chain.base.org/vibenet/explorer` |
 | Base Sepolia (also 8130-enabled) | `https://sepolia.base.org`, chain id `84532` |
 
@@ -42,20 +51,34 @@ reads like a code bug rather than a wrong URL.
 All `api.vibes.base.org` endpoints (RPC proxy, payer, faucet) send permissive
 CORS headers, and so does `rpc.vibes.base.org` — so browser apps can talk to
 either. Prefer `rpc.vibes.base.org` for execution and reserve the `account/rpc`
-proxy for when you specifically want the hosted path.
+proxy for when you specifically want the hosted path. The public RPC is
+method-allowlisted: `eth_getHeaderBy*`, `eth_getBlockReceipts`,
+`eth_sendRawTransactionSync`, `eth_simulateV1` and `txpool_*` answer
+`rpc method is not whitelisted`.
+
+**Only 8130 / 8168 code needs the fork below.** Querying blocks, streaming
+`newHeads`, and sending plain EOA transactions on vibenet work with stock
+`npm install viem`.
 
 The 8130 modules are additive to viem itself, proposed upstream in
-[wevm/viem#5004](https://github.com/wevm/viem/pull/5004) (still an open draft —
-not yet released to npm). Until it ships, they have to be built from the fork
+[wevm/viem#5004](https://github.com/wevm/viem/pull/5004) (open, out of draft —
+not yet merged or released to npm). Until it ships, they have to be built from the fork
 branch the PR is opened from: `chunter-cb/viem` `feat/eip-8130-production`.
 
 **Use the bundled installer** — it does the whole clone→build→link dance, which
 is error-prone by hand:
 
 ```bash
-scripts/setup-viem-8130.sh [APP_DIR]   # defaults to the current directory
+scripts/setup-viem-8130.sh [APP_DIR] [BUILD_DIR]   # APP_DIR defaults to the current directory
 ```
 
+`BUILD_DIR` defaults to `<APP_DIR>/.viem-8130-src` — a full viem monorepo
+checkout with its own `node_modules` (~500 MB). The script appends
+`.viem-8130-src/` to the app's `.gitignore` so a `git add .` can't commit it;
+for several apps, pass one shared `BUILD_DIR` outside them (npm records the
+`file:` path in `package.json`). Node 22 works despite the fork's
+`node >=24.5` engine warning.
+
 When PR #5004 merges and a viem release ships the modules, this collapses to
 `npm install viem@latest` — the imports (`viem/eip8130`, `viem/eip8168`) and
 APIs are unchanged, so no code moves.
@@ -96,8 +119,9 @@ Creating an account derives a CREATE2 address locally — synchronous, zero RPC,
 `eth_getCode` still `0x`. It becomes real as a **side effect of its first
 transaction**, which carries `account.createChange` alongside your actual calls.
 There is nothing else to call. The shortest path from nothing to a deployed
-account is a *sponsored* first tx (no faucet, no funding); the self-paid route
-needs the address funded first. Read deployment state from `eth_getCode`, never
+account is a *sponsored* first tx (no faucet, no funding — for a zero-value
+first tx; sponsorship covers gas, never value); the self-paid route needs the
+address funded first. Read deployment state from `eth_getCode`, never
 from optimistic local state — it decides whether the next tx carries
 `createChange`. Full lifecycle:
 [references/eip8130-accounts.md](references/eip8130-accounts.md).
@@ -124,16 +148,21 @@ Read the reference for your task:
 | **Accounts & transactions** | Create an 8130 smart account, the counterfactual→deployed lifecycle, send batched calls, attribution metadata, gas estimation, reading account state, locking, gotchas | [references/eip8130-accounts.md](references/eip8130-accounts.md) |
 | **Session keys & policies** | Authorize/revoke actors, scopes, SessionPolicy spend limits, config sequences, verifying "silent" changes | [references/session-keys-and-policies.md](references/session-keys-and-policies.md) |
 | **Gas sponsorship** | Sponsor gas with a payer (ERC-8168), gasless onboarding, `send` vs `sign` modes | [references/payer-sponsorship.md](references/payer-sponsorship.md) |
+| **200ms blocks & timing** | Read a block's millisecond timestamp (`timestampMs`), decode the BaseTime deposit / predeploy, stream `newHeads` over WebSocket, send a tx and see which 200ms block it landed in, fix viem polling, migrate from Flashblocks | [references/200ms-blocks.md](references/200ms-blocks.md) |
 
 ## Operating Procedure
 
 1. **Classify the task** using the table above and read the relevant reference
    before implementing.
 2. **Pick the right RPC**: `rpc.vibes.base.org` works from both Node and the
-   browser; `api.vibes.base.org/api/vibenet/account/rpc` is the hosted proxy to
-   the same chain. Never `vibes.base.org` — that host is not an API.
+   browser; `wss://rpc.vibes.base.org/ws` for subscriptions;
+   `api.vibes.base.org/api/vibenet/account/rpc` is the hosted proxy to the same
+   chain. Never `vibes.base.org` — that host is not an API.
 3. **Implement** with explicit chain id, the `scripts/setup-viem-8130.sh`
-   install, and read-back verification for any account-config change.
+   install (8130/8168 only), read-back verification for any account-config
+   change, and an explicit `pollingInterval` (≈100ms) on every receipt wait or
+   block watch — viem's defaults (4000ms, or a 500ms floor) hide the 200ms
+   cadence.
 4. **Deliver** runnable code, install commands, and any manual steps (env
    vars, faucet funding).
 
@@ -145,8 +174,15 @@ Read the reference for your task:
   (upstream PR: [wevm/viem#5004](https://github.com/wevm/viem/pull/5004); API
   surface: `src/eip8130/index.ts`; docs: `site/pages/eip8130`)
 - **Deep guide (chaptered)**: `github.com/chunter-cb/eip-8130-web` (`/guide/*`)
-- **Session-key walkthrough**:
+- **Session-key walkthrough** (names are stale — map `to8130Account` →
+  `toAccount`, `isActor8130` → `isActor`, `sendCalls` → `sendTransaction`; its
+  `managerActor` step is the PolicyManager-as-operator authorize in the session
+  reference):
   [gist.github.com/chunter-cb/bf70c53a5ab6d8361ce7f4215b776114](https://gist.github.com/chunter-cb/bf70c53a5ab6d8361ce7f4215b776114)
+- **200ms blocks (Cobalt)**:
+  [docs.base.org/upgrades/cobalt/200ms-blocks](https://docs.base.org/upgrades/cobalt/200ms-blocks),
+  [migrate-from-flashblocks](https://docs.base.org/upgrades/cobalt/migrate-from-flashblocks),
+  [test-on-vibenet](https://docs.base.org/build-on-base/test-on-vibenet)
 
 ## Installation