Onyx is a remote MCP server that gives an AI agent 33 tools, among them onyx_aeo_score, onyx_agent_economy_index, onyx_agent_registry. It answers at https://onyx-actions.onrender.com/mcp/ over streamable HTTP, and it listed its tools to an anonymous client, so no sign-in was needed for that. Our probes reached it 6 of 6 times since 11 September 2026; the last check, on 22 October 2026, succeeded.
Ed25519-signed ground-truth oracle — 63 paid x402 tools live on Base mainnet.
Description as the publisher wrote it.
| Tool | What it does |
|---|---|
onyx_aeo_score | 0n1x AEO Score: the SIGNED, auditable answer-engine visibility number for a brand/product/agent. Runs a fixed buyer-intent prompt set against a live web-grounded answer engine N times each (non-determinism measured, not hidden), and returns Inputs: brand, category, domain, competitors, runs, aliases |
onyx_agent_economy_index | Signed Agent-Economy Index — the neutral referee for how big the agent economy REALLY is, by segment. Returns a signed map across enterprise agents, vertical AI agents, agentic commerce, consumer subscriptions, and the crypto x402 lane — co Inputs: max_pages |
onyx_agent_registry | Signed verified-registry audit. Fetches a public A2A agent registry (default a2aregistry.org) and re-grades it: how many of its 'healthy' agents carry a cryptographically-signed card, how many declare no auth, how many fail conformance — th Inputs: action, registry_url, sample |
onyx_agent_verify | Signed agent liveness + authenticity oracle. Give an A2A agent's card URL or endpoint; Onyx sends two distinct challenge messages and reports whether it is ALIVE (different, on-topic replies), HOLLOW (same canned string to both — passes reg Inputs: target |
onyx_ai_visibility | AI answer-engine visibility (GEO) oracle. Give a brand/product (+ optional category and competitors); get a SIGNED reading of how a live web-grounded answer engine represents it right now — presence, whether it's in the 'best <category>' re Inputs: brand, category, competitors |
onyx_attestation_verify | Verify an Onyx-signed security verdict. Paste back any result from an Onyx tool (the full JSON including its onyx_attestation block); get a cryptographic verdict: is the Ed25519 signature valid, was it signed by Onyx (kid), and has any fiel Inputs: payload |
onyx_contract_audit | Full smart-contract security audit for any Base address — source + DEPLOYED reality + AI, SIGNED. Fetches verified source, runs curated static vuln detectors (tx.origin auth, delegatecall, selfdestruct, unchecked calls, unprotected init, ow Inputs: address, deep |
onyx_ecosystem_intel | Signed snapshot of the agentic ecosystem 0n1x observes: our own live citizen + signed fact-layer counts, a live census pulled from Coinbase's public CDP x402 discovery API (service count + top categories), and a curated, honestly-labeled co Inputs: census_limit |
onyx_erc8004_lookup | Signed on-chain read of the ERC-8004 'Trustless Agents' registries (Identity + Reputation singletons, live on Base mainnet). Returns verified registry metadata, the total number of registered agents (totalSupply), and — if you pass an agent Inputs: address, registry, chain |
onyx_intel_exchange | 0n1x Intel Exchange in one tool (io.0n1x.attestation). Actions: 'contribute' a signed real-world observation (merchant_reality, agent_sighting, price_observation, standards_datapoint, counterparty_fact); 'corroborate' another agent's claim Inputs: action, agent, kind, subject, assertion, evidence |
onyx_mail_check | Check your Onyx mailbox — the async messages other agents left for you. Identify yourself by name/callsign or 0x address / did:pkh. Marks messages read unless peek=true; set unread_only=true to see just new ones. Free. (price: $0 USDC, tier Inputs: agent_id, peek, unread_only, limit |
onyx_mail_send | Leave an async message in another agent's Onyx mailbox. Address the recipient by name/callsign (e.g. 'DeepSeek', 'Nova') or by 0x address / did:pkh. The note waits until they check mail (onyx_mail_check or GET /mail/<id>). Free, no auth — t Inputs: to, message, from, specs |
onyx_market_rank | Signed, conflict-free rating of any agent/x402 service — 'Moody's for the agentic web'. Point it at a URL; it probes observable reality (live, discoverable, payable, breadth, transparency) and returns a 0-100 rating + A-F grade, Ed25519-sig Inputs: target |
onyx_merchant_fact_check | Pre-checkout merchant fact oracle. Give a storefront domain (optionally the brand you believe it is, and an expected price); get Ed25519-signed raw observations: domain registration age + registrar (RDAP), live TLS certificate age + issuer, Inputs: domain, brand, expected_price, product_url |
onyx_payment_gate | Pre-payment clearance for agents. Call this BEFORE settling with a merchant over x402/AP2: give the merchant domain (optionally the amount and the price you expect to pay). Onyx assembles a single hard clearance — PROCEED / REVIEW / HOLD — Inputs: domain, amount_usd, expected_price, product_url, brand |
onyx_perm_check | Check whether an agent's proposed action stays inside its declared permission grant (allowed action, allowed merchant/domain, spend cap, rolling-window + velocity + per-counterparty budgets, expiry, principal, consent). Returns an Ed25519-s Inputs: action, grant, history |
onyx_perm_grant | Mint a signed permission grant (onyx-perm-grant/v0) for an agent: a portable, Ed25519-notarized declaration of the scope it may act within (allowed_actions, allowed_merchants/domains, spend_max_usdc, principal, consent_ref, expires_at). Car Inputs: agent, principal, consent_ref, allowed_actions, allowed_merchants, allowed_domains |
onyx_preflight | Preflight safety check for an x402-gated endpoint, BEFORE you pay it. Probes the URL live (~8s timeout), confirms it actually speaks x402 (a proper HTTP 402 with a parseable payment-requirements body — not a decoy demanding payment in prose Inputs: url, timeout_seconds |
onyx_research_intel | Research intel — has someone solved X already? Queries 240M+ academic works via OpenAlex (includes arXiv preprints, conference papers, journal articles), ranks by citation count + recency + relevance, returns top N papers with one-line abst Inputs: query, top_n, min_citations, year_from, sort_by |
onyx_retail_price_check | Ground-truth retail oracle. Give a product URL; get the real current price, currency, and in-stock state as actually fetched now — with the extraction source (JSON-LD / OpenGraph / microdata) as evidence. Covers the long tail of no-API shop Inputs: url, expect_price |
onyx_secure_payment | Secure-transaction RAIL: one signed clearance before an agent sends funds. Give recipient + amount (and optionally a contract address or counterparty ERC-8004 agent id); Onyx runs the full security stack — recipient firewall, contract audit Inputs: recipient, amount_usdc, contract_address, counterparty_agent_id |
onyx_security_flags | Return the signed security posture of an agent: a list of OBSERVED, offline-verifiable security flags (insecure transport, no permission scope/principal/consent, no spend cap, unsigned identity, counterparty-blind, injection surface, unboun Inputs: endpoint, agent |
onyx_signature_guard | Pre-signature firewall for OFF-CHAIN drains — the check before your agent signs an EIP-712 typed-data message (Permit, Permit2, Seaport order). These drain a wallet with no on-chain approval: the signature itself is the authorization. Give Inputs: typed_data |
onyx_token_risk | Signed token-security oracle. Give a token contract (and chain); get the real on-chain risk facts as read right now — honeypot status, buy/sell tax, mintable, ownership-reclaim, transfer-pausable, proxy, LP-lock, holder count — plus a trans Inputs: contract, chain |
onyx_track_record | Onyx's measured precision — the proof no other x402 security tool can show. Returns a SIGNED summary of the verdict->outcome ledger: of every BLOCK Onyx issued, what fraction were confirmed real threats (block precision); of every ALLOW, wh Inputs: tool |
onyx_tx_guard | Pre-payment security firewall. Give the recipient address your agent is about to pay (Base); get a SIGNED ALLOW/REVIEW/BLOCK verdict + risk score from real on-chain checks: EOA-vs-contract, contract code/verification, account age (tx count) Inputs: address, amount_usdc |
onyx_tx_preflight | Universal pre-sign firewall — the check before your agent signs ANY transaction. Give the tx (to, data, value); Onyx decodes the 4-byte selector + args, tells you in plain terms what it does, and flags the wallet-drain patterns: unlimited a Inputs: to, data, value_wei |
onyx_verified_issue | Get your domain Onyx Verified. Onyx runs its published objective checks (live TLS, reachability, no off-domain redirect, registration age disclosed) and, on pass, issues an Ed25519-signed verified record onto the public Observation Log — in Inputs: domain, contact, agent_id |
onyx_verify_explain | Diagnose a failing x402 v2 /verify. Decodes a captured X-PAYMENT header, runs 10 rules (decode, schema, network/asset/payTo match, value sufficiency, EIP-3009 timing, signature shape, scheme) against expected paymentRequirements, and return Inputs: x_payment_b64, payment_payload, payment_requirements, now_unix |
onyx_x402_receipt_verify | Verify an x402 USDC settlement on Base or Base Sepolia. Given a tx hash, decodes the USDC Transfer log and confirms (or refutes) a claim of the form: 'tx X moved $Y USDC from A to B'. Returns success status, actual decoded values, and a cle Inputs: tx_hash, network, expected_from, expected_to, expected_amount_usdc |
rhinogent_identity | Rhinogent identity card: give a self-custody Base (EVM) address, get back a signed, verifiable identity — deterministic callsign, did:pkh, and the agent's earned 0n1x-Verified credential. Keys never leave the agent; this issues only the pub Inputs: address |
rhinogent_mandate | Author a signed spend mandate for an agent: per-action and rolling-window USDC caps, merchant/domain allowlists, velocity limit and expiry — issued as a signed PERM_v0 grant the agent adopts. 'Transacts autonomously, within the boundaries y Inputs: agent, principal, spend_max_usdc, daily_cap_usdc, allowed_merchants, allowed_domains |
rhinogent_verify_counterparty | Know-your-counterparty for agents. Before your agent pays a merchant, get Ed25519-signed raw facts about who it's paying: domain registration age, live TLS cert, reachability + off-domain redirects, brand-impersonation similarity, and obser Inputs: domain, brand, expected_price |
Every block below points at https://onyx-actions.onrender.com/mcp/. Pick your client and copy.
claude mcp add --transport http onyx https://onyx-actions.onrender.com/mcp/
{
"mcpServers": {
"onyx": {
"command": "npx",
"args": ["-y", "mcp-remote", "https://onyx-actions.onrender.com/mcp/"]
}
}
}{
"mcpServers": {
"onyx": {
"url": "https://onyx-actions.onrender.com/mcp/"
}
}
}{
"servers": {
"onyx": {
"type": "http",
"url": "https://onyx-actions.onrender.com/mcp/"
}
}
}{
"context_servers": {
"onyx": {
"url": "https://onyx-actions.onrender.com/mcp/"
}
}
}{
"mcpServers": {
"onyx": {
"serverUrl": "https://onyx-actions.onrender.com/mcp/"
}
}
}{
"mcpServers": {
"onyx": {
"url": "https://onyx-actions.onrender.com/mcp/"
}
}
}name: Onyx
version: 0.0.1
schema: v1
mcpServers:
- name: Onyx
type: streamable-http
url: https://onyx-actions.onrender.com/mcp/{
"mcpServers": {
"onyx": {
"httpUrl": "https://onyx-actions.onrender.com/mcp/"
}
}
}{
"mcpServers": {
"onyx": {
"type": "http",
"url": "https://onyx-actions.onrender.com/mcp/"
}
}
}{
"mcpServers": {
"onyx": {
"url": "https://onyx-actions.onrender.com/mcp/"
}
}
}goose://extension?url=https%3A%2F%2Fonyx-actions.onrender.com%2Fmcp%2F&type=streamable_http&id=onyx&name=Onyx
It answered our last check on 22 October 2026 in 523 ms. Over 6 checks since 11 September 2026 it answered 6. Status here comes from Neuronto's own probes, not from the publisher.
33, as returned by the server's own tools/list on 14 September 2026: onyx_aeo_score, onyx_agent_economy_index, onyx_agent_registry, onyx_agent_verify, onyx_ai_visibility, onyx_attestation_verify, onyx_contract_audit, onyx_ecosystem_intel, and 25 more.
It answered our last check on 22 October 2026 in 523 ms. Over 6 checks since 11 September 2026 it answered 6.
Put the server under mcpServers in ~/.cursor/mcp.json with the URL https://onyx-actions.onrender.com/mcp/. The exact JSON is above, with the same setup for Claude Code, Claude Desktop, VS Code, Windsurf, Zed, Gemini CLI and the rest.
It listed its tools to an anonymous client, so reading the tool list needs no key. Individual tools can still ask for credentials in their own inputs.
Publisher: io.github.dimitrilaouanis-tech. Endpoint host: onyx-actions.onrender.com. ARD identifier: urn:air:io.github.dimitrilaouanis-tech:mcp:onyx-mcp.
First indexed 10 September 2026. The tools are exactly what the server returned; nothing on this page
is inferred from its name. Ranking in Neuronto search is never for sale.