Shared kernel for the BlockRun product family. One wallet, one output contract, one config — so every BlockRun tool (blockrun CLI, ClawRouter, Franklin, MCP, the SDKs, clawrouter-codex) reads the same ~/.blockrun wallet and speaks the same machine-readable envelope.

Install

npm install @blockrun/core

What's inside

Output contract (`@blockrun/core/output`)

Agent-native by construction — every command returns the same envelope:

import { ok, err, emit, render } from "@blockrun/core";

emit(ok({ address: "0x…" }, { cost: 0.003, chain: "base" })); // stdout, exit 0
emit(err("payment", "insufficient balance", 402));             // stderr, exit 1
// render(env, "json" | "pretty" | "table" | "ndjson" | "csv")

{"ok":true,"data":…,"meta":{…}} / {"ok":false,"error":{"type","code","message"}}

Wallet (`@blockrun/core/wallet`)

Single source of truth. Resolution order matches @blockrun/llm: env BLOCKRUN_WALLET_KEY | BASE_CHAIN_WALLET_KEY → ~/.blockrun/.session → legacy wallet.key.

import { loadWallet, resolvePrivateKey } from "@blockrun/core";
const w = loadWallet(); // { address, privateKey, source } | null  — key never leaves the machine

Wallets from other applications are never adopted automatically. ~/.<app>/wallet.json files are discoverable, but installing another product — or dropping a file into the home directory — must not be able to change which key BlockRun signs payments with. Adoption is an explicit act, and matching is done on the address derived from the discovered key, so a file cannot claim an address it holds no key for:

import { listDiscoveredWallets, adoptWallet } from "@blockrun/core";

listDiscoveredWallets(); // [{ address, source }] — no private keys, nothing active
adoptWallet("0x…");      // copies it to .session, backing up the outgoing wallet first