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

# GET /.well-known/x402.json

> Service discovery — list of paid tiers, their prices, and the settlement chain.

Free, no payment required.  Returns the live price list — kept in
sync with the actual middleware config so an out-of-band dashboard
can't drift from what the API enforces.

## Request

```bash theme={null}
curl https://x402.aegis-kyt.com/.well-known/x402.json
```

## Response

```json theme={null}
{
  "name":        "Aegis KYT x402 API",
  "description": "Per-address AML labels + risk screening, paid in USDC on Base. Powered by Aegis 4-tier consensus + additional consensus inputs.",
  "services": [
    {
      "endpoint":    "/screen/{chain}/{address}",
      "description": "Per-source labels + Aegis consensus risk score in one call.",
      "price":       "0.10",
      "asset":       "USDC",
      "network":     "base",
      "available":   true
    },
    {
      "endpoint":    "/check-address/{chain}/{address}",
      "description": "Aegis full 4-tier verdict (SDN + consensus + 1-hop + BFS).",
      "price":       "1.00",
      "asset":       "USDC",
      "network":     "base",
      "available":   true
    },
    {
      "endpoint":    "/check-transfer/{chain}/{tx_hash}",
      "description": "Transaction Check (KYT): decode + Tier 4 BFS + policy.",
      "price":       "0.50",
      "asset":       "USDC",
      "network":     "base",
      "available":   true
    }
  ]
}
```

## Schema

| Field                    | Type   | Notes                                                                                                                           |
| ------------------------ | ------ | ------------------------------------------------------------------------------------------------------------------------------- |
| `name`                   | string | Human-readable service name                                                                                                     |
| `description`            | string | One-line marketing copy                                                                                                         |
| `services[]`             | array  | Paid tiers offered by this service                                                                                              |
| `services[].endpoint`    | string | OpenAPI-style path template (`{chain}/{address}` placeholders)                                                                  |
| `services[].description` | string | One-line tier description                                                                                                       |
| `services[].price`       | string | USDC amount as a decimal string (`"0.10"` = \$0.10)                                                                             |
| `services[].asset`       | string | Always `"USDC"` for now                                                                                                         |
| `services[].network`     | string | Friendly network name (`"base"`).  See [networks](/reference/networks) for the full list                                        |
| `services[].available`   | bool   | `false` → tier is advertised so clients can plan against the future shape, but live calls return `503` until ops flips the flag |

## Tier history

* **2026-05-05** — `/label` (`$0.10`) and `/screen/light` (`$0.20`)
  removed.  Their data was merged into the new `/screen/{chain}/{address}`
  tier above for `$0.10`.  Old paths now return 404.
* **2026-04-30** — initial 4-tier launch.

## Conventions

* The `endpoint` strings are **templates**, not regex patterns.  Use
  `{chain}` and `{address}` as placeholders matching the values from
  [networks](/reference/networks).
* The price-list is the SINGLE SOURCE OF TRUTH at runtime — the
  middleware uses the same data to build `payment-required` quotes,
  so what's listed is what you'll be charged.


## OpenAPI

````yaml GET /.well-known/x402.json
openapi: 3.1.0
info:
  title: Aegis KYT x402 API
  description: >-
    Pay-per-call AML API for AI agents.  USDC on Base, no API keys, no account
    creation.  See https://docs.aegis-kyt.com for the full endpoint reference.
  version: 0.2.0
servers:
  - url: https://x402.aegis-kyt.com
    description: Production
security: []
paths:
  /.well-known/x402.json:
    get:
      summary: x402 service discovery
      description: |-
        Advertise tiers + their prices in the format consumed by x402-aware
        clients (matches the schema served by x402.blocksec.ai exactly:
        {name, description, services[]}, where each service has endpoint,
        description, price, asset, network, available).
      operationId: discovery__well_known_x402_json_get
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema:
                additionalProperties: true
                type: object
                title: Response Discovery  Well Known X402 Json Get
              example:
                name: Aegis KYT x402 API
                description: >-
                  Per-address AML labels + risk screening, paid in USDC on Base.
                  Powered by the Aegis 4-tier consensus engine.
                services:
                  - endpoint: /screen/{chain}/{address}
                    description: All labels for the address + consensus risk score.
                    price: '0.10'
                    asset: USDC
                    network: base-sepolia
                    available: true
                  - endpoint: /check-address/{chain}/{address}
                    description: Aegis full 4-tier verdict (SDN + consensus + 1-hop + BFS).
                    price: '1.00'
                    asset: USDC
                    network: base-sepolia
                    available: true
                  - endpoint: /check-transfer/{chain}/{tx_hash}
                    description: >-
                      Transaction Check (KYT) — sync <=30s or 202 + free retry
                      URL.
                    price: '0.50'
                    asset: USDC
                    network: base-sepolia
                    available: true

````