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name: okx-agent-payments-protocol description: "Use when an agent hits HTTP 402 / payment-required, or the user mentions x402, x402Version, X-PAYMENT, PAYMENT-REQUIRED, PAYMENT-SIGNATURE, WWW-Authenticate: Payment, permit2, upto, metered billing, a payment channel / voucher / session, channelId / channel_id, opening / closing / topping up / settling / refunding a channel, a paymentId or a2a_ link, creating / checking a payment link, A2MCP / an A2MCP endpoint, or sending a request to / calling an Agent's endpoint with a concrete endpoint URL. Covers x402 (exact, exact+Permit2, upto, aggr_deferred), MPP (charge / session), and a2a-pay paymentId flows. Any close / topup / settle / voucher / refund near a channel_id or session is an MPP mid-session op. Two-phase quote/pay: payment quote, payment pay --payment-id, decode-receipt. The full bilingual trigger list (including Chinese) lives in the skill body." license: MIT metadata: author: okx version: "4.4.10" homepage: "https://web3.okx.com"

OKX Agent Payments Protocol (Dispatcher)

⚠️ READ FIRST — ZERO-TEXT-ON-TRIGGER + NEVER-SKIP-USER-GATES.

Between detecting a 402 (or any trigger word) and emitting the first user-facing card — the Step A3.5 recommendation card, or the Step A4 confirmation card — output ZERO user-visible text. No "received 402", no "triggered OKX Agent Payments Protocol", no "detected N schemes", no enumeration of schemes / networks / tokens / amounts, no "loading skill" — in any language (the same prohibition applies to the equivalent phrases in any other language). The skill-load tool call may run but emits no surrounding prose.

Exactly one confirmation card runs per payment: A3.5's recommendation card (2+ candidates and user picks yes) OR A4's confirmation card (single candidate, OR user picked an alternative from A3.5's expanded list). Do NOT skip the applicable card under the pretext of "past user preference" / "streamlining" / "already confirmed once" — those preferences do not exist. Do NOT render both cards back-to-back with the same info — after yes on A3.5.5, go straight to Step A5. The next user-visible text after detection MUST be one of the two cards.

Three payment paths, distinguished by HTTP signature: accepts-based 402 (challenge in body for v1 or PAYMENT-REQUIRED header for v2), WWW-Authenticate: Payment 402 (channel-capable, intent="charge" or "session"), and a2a-pay (paymentId-based, no 402). Shared steps below (detect → decode → confirm → wallet check), then dispatch to a reference.

User-facing terminology — IMPORTANT

Rule 1 — Always call it "OKX Agent Payments Protocol", and always render it bolded. Use the exact English term OKX Agent Payments Protocol in user-visible messages regardless of the user's language, and always wrap it in markdown bold (**OKX Agent Payments Protocol**) so the user sees it emphasized. Keep it as a fixed English noun phrase even inside otherwise-Chinese sentences. Reserve protocol literals and internal identifiers for CLI invocations, HTTP headers, JSON payloads, and code — never speak them to the user.

Rule 2 — Do not narrate internal protocol detection. The dispatch logic (which header was detected, which reference is being loaded, which scheme/intent was selected, TEE vs local-key path) is internal — keep it internal. The user only needs to see: (a) what is being paid, (b) what they need to confirm, (c) the result.

Rule 2 carve-out — narrow, alternatives list only. Inside Step A3.5, the literals exact / aggr_deferred / charge may be exposed to the user only in the expanded alternatives list (the list rendered after the user picks "show others"), because at that point the user is explicitly choosing between schemes. They MUST NOT appear in: the default recommendation card, the "N other methods" summary line, status narration, error displays, post-payment summaries, or anywhere else. The recommendation card shows network / token / amount / recipient only — never the scheme name.

Rule 3 — Externally-defined protocol literals stay byte-for-byte exact. The JSON field x402Version, the HTTP headers X-PAYMENT / PAYMENT-SIGNATURE / PAYMENT-REQUIRED / WWW-Authenticate: Payment, and the reference URL https://x402.org MUST appear verbatim wherever the protocol/server requires them — these are externally defined and changing them breaks interop. CLI subcommand names (onchainos payment pay / pay-local / charge / session ... / a2a-pay ...) are this CLI's own surface and may evolve; refer to them by their current name in CLI invocations and code, but never speak them to the user (Rule 2).

Example

(EN) Preparing a payment via the **OKX Agent Payments Protocol**. Here are the charge details — please confirm before I proceed… When narrating in another language, translate this lead line but keep OKX Agent Payments Protocol as a bolded English noun phrase.

Progress narration counts as user-visible — Rules 1-3 still apply.

Long-running flows (decode → confirm → wallet check → sign → replay) tempt status updates. Every progress line ("I'm now…", or its Chinese equivalent) is user-facing; Step labels and reference/scheme names are internal — do NOT echo them. The anchors:

| ❌ Don't say | ✅ Say | |---|---| | "Detected HTTP 402, triggering OKX Agent Payments Protocol" / "Detected PAYMENT-REQUIRED, loading exact" | (silent — detection / routing is internal) | | "CLI selected exact, assembling the PAYMENT-SIGNATURE header" / "taking the TEE path" | "Signing done, replaying the request" | | "Detected 2 schemes: exact (USD₮0), aggr_deferred (USDG)" / "checking balance to filter candidates" | (silent — enumeration + balance check are internal; only the recommendation card is user-visible) | | "Entering session / charge mode" | "Channel opened" — describe the user-visible effect, not the internal mode | | "Per past preference, paying without re-confirming" | (forbidden — no such preference; the gate is mandatory every time) |

The same rules apply when narrating in any other language — match the intent of these ❌/✅ phrasings, not just the English wording.

These rules are authoritative and always in force — when unsure whether a status line leaks internals, match it against the rows above and default to silence.

Triggers (full list)

• EN: 402, payment required, x402, x402Version, X-PAYMENT, PAYMENT-REQUIRED, PAYMENT-SIGNATURE, WWW-Authenticate: Payment, permit2, upto, metered billing, open / close / topup / settle channel, voucher, session payment, channelId, channel_id, paymentId, a2a_, create payment link, payment link, payment status
• subscribe / subscription / recurring payment / recurring charge / "pay every month" / cancel subscription / upgrade plan / downgrade plan → period scheme (see references/subscription.md)
  • ⚠️ EXCEPT when the message contains jobId / subId / ASP / provider / trial / renew / deliver / periodCount / subscription task — those are Agent Commerce subscription tasks (monthly service agreements), route to okx-ai instead.
• The same trigger vocabulary applies to its equivalents in any other language (e.g. Chinese subscription / recurring-billing terms route to the period scheme the same way).
• Carve-out: AI-service/ASP subscriptions from the agent marketplace (context: ASP / Agent#N / 任务 / 试用期 / 服务方; NO 402 offer / resource URL / paymentId) belong to okx-ai (onchainos agent my-subscriptions / subscribe-detail), NOT the period scheme. For a bare "my subscriptions / 我的订阅" with neither signal, ask the user once instead of assuming period.

Any close / topup / settle / voucher / refund near a channel_id or session context = MPP mid-session op → references/session.md.

Pre-flight Checks

Read ../okx-agentic-wallet/_shared/preflight.md (fallback: _shared/preflight.md).

Command Routing & Reference map

Each 402 signal (or paymentId) → CLI command → reference. Detailed gating + decode/confirm steps are in Path A / Path B below.

| Signal | Command | Reference | |---|---|---| | 402 + PAYMENT-REQUIRED (v2) / body x402Version (v1) — one or many accepts[] schemes (exact / exact+Permit2 / upto / aggr_deferred) | Primary — Path A: payment quote <url> → confirm → payment pay --payment-id --yes. Single-scheme and multi-scheme take the same quote flow (the CLI decodes, converts, balance-checks, signs, replays, and returns the receipt). Even if you already curled the raw 402, re-enter via payment quote <url> — never assemble a header by hand and never jump straight to sign-only. Compat only: payment pay --payload [--selected-index] (sign-only + manual replay) when quote is unavailable. | Success path loads no reference. references/accepts-schemes.md only for: post-pay scheme-specific receipt reading, Permit2 allowance insufficient one-time approve, pay-local, the pay --payload compat path, or legacy x402 v1 (the CLI-output field tells you which scheme — permit2Authorization = upto / exact+Permit2, sessionCert = aggr_deferred, authorization = exact) | | 402 offer with an accepts[] entry whose scheme == "period" (a.k.a. permit2_subscription) — recurring/subscription billing | payment subscription subscribe/access/change/cancel/cancel-pending/my-subscriptions/allowance-status | references/subscription.md | | 402 + WWW-Authenticate: Payment, intent="charge" | payment charge --challenge | references/charge.md | | 402 + WWW-Authenticate: Payment, intent="session" (or mid-session channel_id) | payment session open/voucher/topup/close | references/session.md | | paymentId / a2a_… link / create-or-check payment link | payment a2a-pay create/pay/status | references/a2a_charge.md | | A2MCP / 402 endpoint URL, "pay this endpoint", entry A/B payment node | payment quote <url> [--param k=v ...] [--method GET \| POST \| ...] | (inline — Path A) | | A2MCP MCP-transport endpoint (URL ends /mcp or /sse, returns text/event-stream / JSON-RPC, or you have a tool name) | payment quote <url> (discovery → mcpTools[]) → payment quote <url> --tool <name> --param k=v (trigger 402) → payment pay --payment-id <id> --yes | references/a2mcp-mcp.md | | User confirmed the quoted payment (currency/amount/scheme chosen) | payment pay --payment-id <id> [--selected-index <n>] --yes | (inline — Path A) | | Need to decode a PAYMENT-RESPONSE header or a charge receipt | payment decode-receipt (--header <b64> \| --receipt <json>) | (inline — read-only) |

Don't load a reference on the success path. On the primary Path A flow, onchainos payment pay --payment-id --yes signs, replays, and returns the settled receipt directly — skip references/accepts-schemes.md entirely (this holds for a single accepts[] scheme exactly as for multi-scheme). On the compat pay --payload path the CLI returns an authorization_header you replay yourself — same rule, no reference on success. Load references/accepts-schemes.md only on a failure / legacy path: Permit2 allowance insufficient → references/accepts-schemes.md (one-time approve), or a legacy x402 v1 raw proof → its "Legacy: x402 v1" section. charge / session / a2a_charge are always loaded — those are multi-phase flows.

Channel mid-session ops (close / topup / settle / voucher / refund mentioned with an active channel_id, regardless of fresh 402) → stay here, jump straight into references/session.md at the matching phase. Do NOT search for a separate close-channel / topup-channel / settle-channel tool — they're all onchainos payment session ... subcommands.

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Path A: HTTP 402

Path A (accepts-based): quote → confirm → pay — PREFERRED 2-round flow

**For an accepts-based 402 / A2MCP endpoint, the CLI does all m