evernode-mcp — Evernode AI Builder

A Model Context Protocol server that lets an AI agent build, check, cost, and deploy HotPocket dApps on Evernode / Xahau. Point any MCP-capable agent (Claude, etc.) at it and ask for a dApp — it scaffolds a contract from templates written to avoid the known consensus-breakers, lints contract code for non-deterministic patterns, estimates the EVR lease, ranks live Evernode hosts, generates the deploy commands, and — when the dApp moves value on Xahau — emits the commands to install a spend-limit Hook and prove its invariant with the Hooks toolchain.

HotPocket is Evernode's contract runtime: it runs your Node.js/WASM contract on every node of a cluster and puts the output + state through consensus. The single biggest beginner mistake is non-deterministic code (Date.now(), Math.random(), fetch(), …) — two nodes compute different results and the ledger stalls. This server is built around catching the common causes of that before deploy (heuristically — see what it does / doesn't catch).

It is advisory and read-only: it generates files + guidance, never holds keys, never spends EVR, never acquires a lease, never signs or submits, and it connects to the Offledger Cluster Manager rather than replacing its orchestration. No API keys or accounts are needed; the only network calls are read-only HTTPS GETs to the public OnLedger API from two tools (see Network access).

Where it fits — the layer-2 companion to the Hooks trifecta

The Hooks pipeline secures layer-1 Hooks — write → simulate one tx → prove all inputs → watch live:

evernode-mcp is the layer-2 companion: it builds the HotPocket dApps that run on Evernode hosts. Whenever a dApp settles value on Xahau through a Hook-guarded account, it hands off to the trifecta — it never re-asserts settlement safety itself (check_hook_compat / generate_settlement emit the trifecta's prove/install commands, not a safety verdict).

Related MCP server: XRP Ledger Testnet MCP Server

Tools

All twelve tools are read-only / advisory. Every tool sets readOnlyHint: true; only the two live OnLedger tools (recommend_hosts, host_diagnostics) set openWorldHint: true (they may reach a live external endpoint, OnLedger). Each tool publishes an output schema, so an agent gets a validated structuredContent shape (not just text) — no guessing field names.

Templates

generate_contract ships 10 templates. Each is written to avoid the known non-determinism sources (no wall-clock, no randomness, no network in the contract path; time is the consensus ledger seq ctx.lclSeqNo; state persists only through the contract's own consensused state file) and is lint-clean: the smoke test and the suite run every template through check_determinism (no HIGH findings) and check_contract_api. That is a heuristic check, not a proof of determinism — test on a multi-node cluster before mainnet.

Each generated file set carries notes including "before deploy: run check_determinism on src/index.js — HIGH findings break consensus."

Why the determinism check matters (and exactly what it does / doesn't catch)

HotPocket consensuses contract output across every node. If two nodes diverge — because you called Date.now(), Math.random(), fetch(), or read process.env, or iterated an unordered collection built in a non-consensused order — consensus breaks and the ledger stalls. check_determinism flags these before you deploy.

It is a heuristic linter, not a prover — a source scan (mostly per-line regex, plus a small cross-line alias pass), so it is guidance, never a guarantee. Design bias (deliberate): for this tool a false-negative (silently missing a real consensus breaker) is the worst outcome, so when a construct could iterate/serialize an unordered collection but can't be proven sorted, it is flagged. A false-positive (flagging safe code) only costs you a justification.

Now covered (each with a why + a concrete fix):

• Wall-clock — Date.now, performance.now, process.hrtime[.bigint], new Date() (HIGH).

• Randomness — Math.random, crypto.randomBytes/randomUUID/randomInt/randomFill[Sync]/getRandomValues (HIGH).

• Network I/O — fetch/axios/got/node-fetch, require('https'|'net'|'dns') (HIGH).

• Per-node env — process.env/process.pid, os.hostname/networkInterfaces/cpus/freemem/loadavg/uptime/userInfo/platform/arch/tmpdir/endianness (HIGH).

• Timers / race — setTimeout/setInterval/setImmediate, Promise.race/any (MEDIUM).

• Filesystem — fs.read*/write*/stat/readdir outside the sanctioned state file (MEDIUM).

• Unordered iteration — for..in, and Object.keys/values/entries + Map/Set for..of (LOW). Sorted views (Object.keys(o).sort(), Object.entries(o).sort(...)) are recognized and not flagged.

• Aliased Map/Set (LOW) — a variable or a member (this.m = new Map(), state.m = new Set()) bound to new Map()/new Set() then iterated / spread / forEach'd / Array.from'd / .entries()/.keys()/.values() on a later line (the cross-line alias pass — now covers member-expression aliases, not just plain identifiers).

• Member-expression for..of (LOW) — for (const x of this.m / state.m / obj.m) even with no Map/Set evidence: order-unprovable, so flagged. Known deterministic array members (user.inputs/outputs) and call expressions (ctx.users.list()) are recognized and not flagged.

• Spread / Array.from materialization (LOW) — [...map], [...Object.values(o)], Array.from(set) that materialize insertion order into an array; suppressed when immediately .sort()-ed.

• .forEach (LOW) — over an Object view or new Map/Set; suppressed when sorted first.

• JSON.stringify of an unordered object (LOW) — a bare object identifier or a spread/merge whose key order isn't provably consensused (the serialized output/state is consensused byte-for-byte). Fixed-key object literals, arrays, primitives, a sorted replacer array, and .sort()-ed arguments are recognized as safe and not flagged.

• Locale / timezone / ICU (MEDIUM) — toLocaleString / toLocaleDateString / toLocaleTimeString, localeCompare, and Intl.*. These depend on the host's locale + ICU collation/format data (and timezone), which differ across nodes — the produced string or sort order diverges. Fix: locale-independent formatting + a code-point comparison (a < b ? -1 : a > b ? 1 : 0), never localeCompare.

• Floating-point literals (LOW) — a non-integer float literal (e.g. 0.1, or a negative-exponent scientific literal 1.5e-3 / 1e-3) or parseFloat( feeding contract math: float rounding / NaN / -0 can differ across engines/hosts. Fix: integer math only (work in drops, Math.floor(a*n/d)). Integer literals, integer-valued positive-exponent literals (1.5e3 = 1500), and integer division/floor are not flagged.

Still out of scope (documented honestly — these are NOT caught):

• Bare float math / untyped division — a / b of two unknown-typed variables (no float literal / parseFloat signal) is too noisy to flag soundly, so it isn't. Only float literals and parseFloat are flagged.

• Deeper data-flow — order divergence behind multi-hop aliases (const n = m), function-return values (const m = makeMap()), Map passed in as a parameter, object spreads merged across several statements, dynamically-built call expressions, or a Map reached through a separate-statement reassignment (let m; m = new Map()). The alias pass covers the direct const x = new Map() and the direct member this.m = new Map() cases, not arbitrary data-flow.

• Known acceptable false-positives — e.g. [...Object.keys(o)].sort() still fires the base iteration-order rule (the spread hides the .sort() from it); a Date.now() used only for a local log; an order-independent reduction over a Map; an honest array iterated as for (const x of this.list) (a member with no array-allowlist entry). These flag safe code (the acceptable direction) — justify or refactor.

So: it catches the breakers beginners hit, and biases toward over-flagging the iteration/serialize classes — it does not prove determinism. Settlement safety is proven separately by the trifecta (xahc-prover). Always test on a real multi-node cluster before mainnet.

Settlement → the trifecta handoff

When a value-moving dApp (escrow / subscription payout / payment_splitter) pays out on Xahau, it does so from the cluster's multisig account. generate_settlement produces a three-part bundle:

1. Cluster-side payout code (xahau/settle.js, a starting point) — the contract decides amounts under consensus; signing happens OUTSIDE consensus via the cluster's threshold/multisig signer. The generated file signs with a single key as a placeholder; replace it with multisig aggregation.

2. The install of the reference agent_guardrail Hook (from xahc-prover; exercised on Xahau testnet) on the cluster account, with your per-tx LIM (spend cap, 8-byte big-endian HookParameter) + optional DST (destination lock) — emitted as an unsigned xahc install-tx SetHook to sign offline.

3. The exact xahc prove command to prove the guardrail invariant on your built WASM.

The bundle emits the prove/install commands — it does not assert a safety verdict itself. While the Hook is installed, an outgoing Payment over LIM or to a non-allowed DST is rejected by the ledger even if the payout code or a signer is wrong. Limits: the Hook fires on Payment only, so it does not stop the account's signers from removing it (SetHook) or moving value with other transaction types — protect the signer quorum. A PROVEN verdict from xahc prove holds within the prover's modeled scope; deploy only on PROVEN for your build.

Install

Requires Node.js 20+. The server speaks MCP over stdio; your MCP client launches it.

From npm

npx -y evernode-mcp --help      # run without installing (prints usage and exits)
npm install -g evernode-mcp     # or install the `evernode-mcp` command globally
evernode-mcp --smoke            # offline self-test (templates lint-clean, checker + math work)

Run with no arguments, evernode-mcp waits for an MCP client on stdin/stdout — it is not an interactive CLI.

Add it to an MCP client

Claude Code:

claude mcp add evernode -- npx -y evernode-mcp

Claude Desktop (claude_desktop_config.json), or any client that takes an mcpServers block:

{
  "mcpServers": {
    "evernode": { "command": "npx", "args": ["-y", "evernode-mcp"] }
  }
}

If you installed globally, "command": "evernode-mcp" with no args works too. No environment variables, API keys, or wallet are needed.

From GitHub / source

npm install -g github:Hugegreencandle/evernode-mcp   # builds on install via `prepare`

Or clone and build:

git clone https://github.com/Hugegreencandle/evernode-mcp && cd evernode-mcp
npm install        # the `prepare` script compiles dist/ automatically
npm run smoke      # offline self-test
npm test           # the full Vitest suite (offline)

Network access

Ten of the twelve tools are fully offline. Only recommend_hosts and host_diagnostics make network calls, and only when you don't supply host data yourself:

OnLedger is a third-party service, not run by this project; its data is only as current as its index. On any failure the tools return an empty result with a note — never fabricated hosts. Nothing is ever written to a ledger. (The generated xahau/settle.js file connects to wss://xahau-test.net when you run it; the server itself never does.)

Usage

Point any MCP-capable agent at the server and just ask, e.g.:

• "Scaffold an escrow HotPocket dApp called vault." → generate_contract

• "Is this contract safe for cluster consensus?" (paste source) → check_determinism

• "Does this contract use the HotPocket API correctly?" (paste source) → check_contract_api

• "Scaffold an oracle dApp that agrees on a price via NPL." → generate_contract (oracle_consumer)

• "Is host rHostAddr… healthy enough to lease?" → host_diagnostics (live)

• "What pattern should I use for a token-gated forum?" → recommend_pattern

• "Find me the 5 cheapest active Evernode hosts in Germany." → recommend_hosts (live)

• "Estimate the EVR to run a 3-node cluster for 720 moments at 2 EVR/moment." → estimate_lease_cost

• "Generate the safe Xahau settlement for my splitter, capped at 50 XAH." → generate_settlement → then run the emitted xahc prove command.

Dev / test / CI

npm run build      # tsc → dist/
npm test           # build + Vitest (offline; mocks the live OnLedger fetch)
npm run smoke      # node dist/index.js --smoke — offline self-test
node dist/index.js # run as a stdio MCP server

• Tests (tests/): determinism (rule coverage incl. the regression floor + new gaps), contractApi (good contract clean + each API-misuse flagged), advisor (lease math, host ranking, error mapping, pattern/deploy branches), templates (per-template build + determinism-clean + per-template invariants), settlement (LIM encoding + trifecta handoff shape), outputSchemas (each handler's real output validates against its published schema), index (end-to-end: every tool driven through an in-memory MCP client, input-schema rejection), hostDiagnostics (healthy / red-flag / not-found / fetch-failure honesty, mocked fetch), and fetch (live-path hardening, mocked).

• CI (.github/workflows/ci.yml): on push + PR to main, runs npm ci, npm run build, npm test, and npm run smoke on Node 20.

• createServer() is exported from src/index.ts so the server can be driven over an in-memory transport in tests without starting the stdio transport.

Honest scope (recap)

• Generates code + guidance; does not acquire leases, sign, or move EVR/XAH. No key custody.

• recommend_hosts fetches live from OnLedger (or ranks a list you supply) — it never fabricates host addresses/specs; on fetch failure it returns empty hosts + a note explaining why, never a fabricated fallback.

• check_determinism and check_contract_api are heuristic source scans (mostly per-line regex) — guidance, not a proof; check_determinism is biased to over-flag the iteration/serialize classes and has documented blind spots (bare float math, multi-hop data-flow). Test on a real multi-node cluster before mainnet.

• Settlement safety (Hook spend limits) is delegated to the Hooks toolchain (xahc prove) — this server emits the prove/install commands, never a verdict. The guardrail Hook covers outgoing Payments only.

• generate_deploy_commands and explain_error are static guidance. The command syntax was checked against evdevkit 0.7.22 and hpdevkit 0.6.9 (npm, 2026-10-01); check the Evernode docs or --help if your version differs.

• estimate_lease_cost is arithmetic on the rate you supply; hosts set their own rates.

License

MIT © 2026 Dane Brown. Open source; see LICENSE. Not affiliated with Evernode Labs or the Xahau project. check_determinism findings are heuristic guidance, not a guarantee — always test on a multi-node cluster and review before mainnet.