> ## Documentation Index
> Fetch the complete documentation index at: https://docs.rail402.dev/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> Rail402 is an x402 payment facilitator, Stellar-native Bazaar discovery layer, and agent tooling for the Stellar network. It currently targets stellar:testnet.
> The live testnet facilitator is https://facilitator.rail402.dev with endpoints /verify, /settle, /supported, /health, and /discovery/*.
> Payment amounts use 7-decimal SEP-41 integer (stroop) arithmetic. Never use floating-point math for amounts.
> Every rejection returns a machine-readable error code and a non-null human-readable reason. When explaining a failure, surface both.

# Prometheus metrics (text/plain)

> Series: `x402_explorer_payments_total`, `x402_explorer_facilitators`,
`x402_explorer_payments_by_scheme{scheme}`, `x402_explorer_payments_by_confidence{confidence}`,
`x402_explorer_polls_total`, `x402_explorer_events_seen_total`,
`x402_explorer_transactions_fetched_total`, `x402_explorer_payments_ingested_total`,
`x402_explorer_rpc_failures_total`, `x402_explorer_backfill_pages_total`,
`x402_explorer_last_ledger{network}`, `x402_explorer_horizon_pages_total`,
`x402_explorer_horizon_inserted_total`.




## OpenAPI

````yaml /api-reference/explorer.openapi.yaml get /metrics
openapi: 3.1.0
info:
  title: Rail402 Explorer API
  version: 0.1.0
  summary: x402 payments explorer for Stellar
  description: >
    Read-only public API over x402 payment activity observed on Stellar. The
    explorer watches the

    ledger directly (Soroban RPC + Horizon), classifies x402 settlements
    structurally — no

    facilitator registration is required for a payment to appear — attributes
    each payment to the

    facilitator that submitted it, and enriches sellers via the x402 Bazaar.


    **Amounts** are stroop-scale integer strings (7 decimals). Every amount
    field has a

    `…Decimal` companion for display; never do arithmetic on the decimal form.


    **Confidence tiers** (every payment carries one; inference is never
    presented as fact):

    - `rail402` — submitted by the Rail402 deployment's published signer.

    - `verified-facilitator` — submitter matches a registered facilitator's live
    `/supported` signers.

    - `x402-shaped` — structurally an x402 settlement, submitter unknown.


    **History**: the full Soroban RPC retention window (~7 days) is backfilled
    for all

    facilitators including unknown ones, and every registry-verified
    facilitator's complete

    chain-epoch history (back to the 2025-12-17 testnet reset) is recovered from
    Horizon.

    Horizon-recovered rows have no `asset`/`assetCode` (that string only exists
    in event data);

    `assetContract` is always present.


    **Errors** are always `{ code, reason, retryable, details? }` — branch on
    `code`, never parse

    `reason`. CORS is open (`*`): browsers may call this API directly.
servers:
  - url: https://explorer-explorer.up.railway.app
    description: stellar:testnet
security: []
tags:
  - name: payments
    description: The payment stream and per-transaction detail
  - name: entities
    description: Sellers and facilitators
  - name: registry
    description: Facilitator self-registration
  - name: ops
    description: Health and metrics
paths:
  /metrics:
    get:
      tags:
        - ops
      summary: Prometheus metrics (text/plain)
      description: >
        Series: `x402_explorer_payments_total`, `x402_explorer_facilitators`,

        `x402_explorer_payments_by_scheme{scheme}`,
        `x402_explorer_payments_by_confidence{confidence}`,

        `x402_explorer_polls_total`, `x402_explorer_events_seen_total`,

        `x402_explorer_transactions_fetched_total`,
        `x402_explorer_payments_ingested_total`,

        `x402_explorer_rpc_failures_total`,
        `x402_explorer_backfill_pages_total`,

        `x402_explorer_last_ledger{network}`,
        `x402_explorer_horizon_pages_total`,

        `x402_explorer_horizon_inserted_total`.
      operationId: getMetrics
      responses:
        '200':
          description: Prometheus exposition format 0.0.4
          content:
            text/plain: {}

````