Evernode

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 deterministic-by-construction contract, heuristically checks it won't break cluster consensus, estimates the EVR lease, ranks live Evernode hosts, generates the deploy commands, and — when the dApp moves value on Xahau — hands the settlement Hook off to the trifecta to be proven safe.

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 that.

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.

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:

stage	tool	what it does
write	xahc	author + compile a safe Hook to clean, lint-passed WASM
simulate one	xahau-mcp	run the real bytecode against one live transaction
prove all	xahc-prover	prove an invariant holds for every input in scope — or return the counterexample
watch live	xahc-watch	bind a proof to the deployed hook and continuously attest it (alerts on a SetHook swap or a live verdict break)

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).

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.

tool	open world?	returns
list_templates	no	{ templates } — the 10 available dApp template names.
generate_contract	no	{ template, files, notes } — a complete, determinism-clean HotPocket file set (contract + state helper + hp.cfg.override + package.json + client) for a template.
check_determinism	no	{ findings, summary } — the differentiator. A heuristic scan of contract source for non-deterministic patterns (wall-clock, randomness, network I/O, env/host reads, timers, unordered iteration, locale/timezone formatting, floating-point literals) that break cluster consensus. Each finding has line/column/rule/severity/why/fix. HIGH findings are likely consensus breakers. Guidance, not a proof.
check_contract_api	no	{ findings, summary } — sibling to check_determinism (same honest framing — guidance, not a proof). A heuristic static check that a HotPocket Node.js contract uses the contract API correctly: an hpc.init(...) entry point, reading ctx (users/lclSeqNo), persisting ONLY through the consensused state mechanism (no arbitrary fs writes to non-state paths), handling ctx.users I/O, using ctx.lclSeqNo for time (not Date.now), and awaiting async consensus ops. Each finding has line/column/rule/severity/why/fix.
recommend_pattern	no	{ pattern, nodes, notes } — given a plain-English use-case, the HotPocket pattern: node count, state model, oracle/NPL usage, Xahau settlement, and the determinism caveats that matter.
check_hook_compat	no	{ involvesHook, workflow, repos } — when a dApp settles via a Xahau Hook, the exact write → simulate → prove handoff to the trifecta (xahc · xahau-mcp · xahc-prover).
generate_settlement	no	{ template, limitDrops, files, install, prove, notes } — cluster-side Xahau payout code + the install of the trifecta's PROVEN agent_guardrail Hook (per-tx LIM + optional DST lock) + the exact xahc prove command. "Safe by construction → proven safe": the ledger enforces the cap even if the contract/signer is wrong. Accepts escrow / subscription / payment_splitter / streaming_payment / multisig_treasury.
estimate_lease_cost	no	{ inputs, perNodeEVR, totalEVR, approxDurationHours, notes } — tenant EVR lease = evrPerMoment × moments × nodes. Honest: rates are host-set (no network standard); host-side registration fees are excluded.
recommend_hosts	yes	{ mode, ranked, prefer, note, source?, query? } — fetch + rank live Evernode hosts from OnLedger (real-time from the Xahau registry hook) by cheap / capacity / reputation, with filters (min reputation/slots/RAM, country) — or rank a hosts list you supply. Real data only — never invents hosts; honest empty + note on fetch failure.
host_diagnostics	yes	{ found, address, source, note?, registration?, reputation?, slots?, lease?, specs?, redFlags } — health view of a single Evernode host by r-address: registration status, reputation, active/total/available slots, lease terms (rate/drops if available), specs, and red-flags (low reputation, full capacity, flagged/stale). Fetches live from OnLedger — or diagnose a host object you supply. Real data only: numeric fields are soundly coerced (a string-typed numeric like "252" becomes a real number; garbage / non-finite values are omitted, never a fabricated 0); unknown fields are omitted (never invented); honest found:false + note on not-found / fetch failure.
generate_deploy_commands	no	{ steps, notes } — command sequences for local (hpdevkit dev cluster) · single (evdevkit acquire one host) · cluster (evdevkit N-node) · cluster-manager (connect to the Offledger Cluster Manager).
explain_error	no	{ matched, explanations? / message? } — map a HotPocket/Evernode error to cause + fix (connection, consensus stall, no hosts, insufficient EVR, lease expiry, docker/Sashimono, Hook rejection).

Templates

generate_contract ships 10 templates. Each is deterministic by construction (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 dogfooded clean through check_determinism (no HIGH findings) and check_contract_api by the smoke test and the suite.

template	what it is	determinism note
blank	minimal echo contract — a starting point.	echoes input + ctx.lclSeqNo.
escrow	depositor locks an amount-claim for a beneficiary, released after a deadline.	deadlines are ledger sequences, not timestamps.
subscription	users subscribe for N ledger-rounds; access granted while lclSeqNo < expiry.	pure ledger-seq accounting.
game_backend	turn-based per-user scores + leaderboard.	leaderboard sorts with a code-point pubkey tiebreaker (not localeCompare — host ICU collation diverges) so ordering is deterministic.
voting	one-vote-per-pubkey poll with tally.	tally iterates a sorted key view; votes keyed by pubkey dedupe.
token_gated	gated access via an admin-maintained allowlist.	does not read an on-chain balance from contract logic (non-deterministic) — uses a consensused allowlist/oracle attestation.
payment_splitter	records deposits, computes weighted splits in integer drops.	remainder to the last recipient so payouts sum exactly (no rounding leak); actual payout is a separate Xahau multisig step (see generate_settlement).
oracle_consumer	the canonical hard pattern: brings external data in via NPL agreement (nodes agree on the value before acting), never a direct fetch.	nodes PROPOSE their observation over the Node Party Line and only ACT on a strict-majority agreed value (a primitive, so its canonical form is byte-identical); disagreement is a deterministic no-op; the agreed datum is stamped with ctx.lclSeqNo.
streaming_payment	per-ledger-seq vesting: releasable amount is release = f(ctx.lclSeqNo).	pure function of the consensus clock, integer drops only (no float divergence); the contract RECORDS the release — the actual transfer is deferred to generate_settlement.
multisig_treasury	records spend proposals + M-of-N approvals (threshold).	approvals keyed by signer pubkey, counted over a sorted view; on reaching the threshold it emits the settlement step to generate_settlement (ties the trifecta in) — the contract never signs/spends.

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 the "safe-by-construction → proven-safe" bundle:

1. Cluster-side payout code (xahau/settle.js) — the contract decides amounts deterministically under consensus; signing happens OUTSIDE consensus via the cluster's threshold/multisig signer (no single node holds spend power).
2. The install of the trifecta's already-proven, testnet-validated agent_guardrail Hook 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. Even a buggy or compromised signer set cannot exceed the LIM or pay a non-allowed DST: the ledger rejects it. Deploy only on a PROVEN verdict from xahc prove.

Install

Install straight from GitHub — it builds on install (the prepare script runs tsc):

npm install -g github:Hugegreencandle/evernode-mcp

Or clone and build:

git clone https://github.com/Hugegreencandle/evernode-mcp && cd evernode-mcp
npm install        # `prepare` compiles dist/ automatically
npm run smoke      # offline self-test (templates determinism-clean, checker + math work)
npm test           # the full Vitest suite (offline)

Add to an MCP client (e.g. Claude Code / Desktop):

{ "mcpServers": { "evernode": { "command": "evernode-mcp" } } }

Or point it directly at the built entry:

{ "mcpServers": { "evernode": { "command": "node", "args": ["/path/to/evernode-mcp/dist/index.js"] } } }

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 is a heuristic source scan — guidance, not a proof; biased to over-flag the iteration/serialize classes; test on a real multi-node cluster before mainnet.
• Settlement safety (Hook spend limits) is delegated to the trifecta, which proves it — this server emits the prove/install commands, never a verdict.

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.