okx/onchainos-skills/okx-agent-payments-protocol

OKX Agent Payments Protocol (Dispatcher)

For an active marketplace A2MCP invocation started by agent a2mcp invoke, follow ../okx-ai/references/a2mcp/invoke.md through confirmation, payment, and result presentation. Its bound paymentId does not start a new generic quote or confirmation flow here.

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 "Don't say" / "Say" examples, 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)
• Exception: when the message contains jobId / subId / ASP / provider / trial / renew / deliver / periodCount / subscription task, it is an Agent Commerce subscription task (monthly service agreement); 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.

Preflight

Preflight checks: At the start of each thread, complete the checks in ../okx-agentic-wallet/_shared/preflight.md. If missing, read _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.

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.

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 mechanical work. You do exactly two reasoning rounds. (For WWW-Authenticate: Payment charge / session challenges, skip this and use the protocol-detection steps below.)

Step A1 — Extract params (round 1)

From the user prompt (Entry A) or the task payment node (Entry B), extract the endpoint url and any known business params. Do NOT curl, decode, or convert anything yourself.

Step A2 — Quote

Run: onchainos payment quote <url> [--param key=value ...] [--method GET|POST|...] The CLI probes the endpoint, parses the 402, checks your wallet balance, ranks candidates, and writes a paymentId.