> ## Documentation Index > Fetch the complete documentation index at: https://docs.useselo.xyz/llms.txt > Use this file to discover all available pages before exploring further. # Get a preflight > Read a stored preflight, eligible or not, with status 200. The response is not re-evaluated: compare `expiresAt` with the current time before paying. ## OpenAPI ````yaml /openapi.json get /v1/preflight/{preflightId} openapi: 3.1.0 info: title: Selo API version: 1.0.0 summary: CI for x402. It pays your endpoint before your users do. description: >- Selo is a release gate for paid x402 APIs on Algorand. You authorize your endpoint, run a free preflight, then pay Selo 1.00 USDC over x402. Only after that payment settles does Selo pay your endpoint as a real x402 client, run five release checks and return a deterministic PASS, FAIL or INCONCLUSIVE verdict with an Ed25519-signed attestation. There are no API keys. Access to a target is granted per target by authorization; the only paid route is `POST /v1/release-test`, paid with x402. Bodies are JSON, at most 64 KiB. contact: name: Selo url: https://useselo.xyz servers: - url: https://api.useselo.xyz description: Production, Algorand Mainnet security: [] tags: - name: Authorizations description: Prove you control the target before Selo sends it anything. - name: Preflight description: Check for free that a target can be tested and is within budget. - name: Release tests description: The paid x402 route that runs the release checks. - name: Reports description: Private, token-addressed reports of finished release tests. - name: Attestation keys description: Public keys that verify signed verdicts. - name: Discovery description: Machine-readable descriptions of Selo. - name: Health description: Liveness. paths: /v1/preflight/{preflightId}: get: tags: - Preflight summary: Get a preflight description: >- Read a stored preflight, eligible or not, with status 200. The response is not re-evaluated: compare `expiresAt` with the current time before paying. operationId: getPreflight parameters: - name: preflightId in: path required: true description: >- Preflight ID returned by `POST /v1/preflight`. A value that is not a well-formed ID returns 404. schema: type: string pattern: ^pfl_[0-9A-HJKMNP-TV-Z]{26}$ example: pfl_… responses: '200': description: The stored preflight. content: application/json: schema: $ref: '#/components/schemas/PreflightResponse' examples: eligible: summary: Eligible value: eligible: true preflightId: pfl_… target: url: https://api.example.com/v1/orders method: POST priceUsdc: '0.01' estimatedMaxSpendUsdc: '0.01' seloPriceUsdc: '1.00' expiresAt: '2026-10-26T12:15:00.000Z' ineligible: summary: NO_PAYMENT_CHALLENGE value: eligible: false preflightId: pfl_… reason: NO_PAYMENT_CHALLENGE message: >- The target did not answer the unpaid request with a valid x402 challenge '404': description: No preflight with this ID. content: application/json: schema: $ref: '#/components/schemas/ApiError' examples: NOT_FOUND: summary: Unknown ID value: error: NOT_FOUND message: Preflight pfl_… does not exist '500': $ref: '#/components/responses/InternalError' components: schemas: PreflightResponse: oneOf: - $ref: '#/components/schemas/PreflightEligible' - $ref: '#/components/schemas/PreflightIneligible' ApiError: type: object description: Error body returned by every failing request. required: - error - message properties: error: type: string description: Stable machine-readable error code, for example `VALIDATION_FAILED`. message: type: string description: Human-readable explanation. Do not parse it. PreflightEligible: type: object description: >- The target can be tested. Pass `preflightId` to `POST /v1/release-test` before `expiresAt`. required: - eligible - preflightId - target - estimatedMaxSpendUsdc - seloPriceUsdc - expiresAt properties: eligible: type: boolean const: true preflightId: type: string description: '`pfl_` plus 26 Crockford base32 characters.' target: type: object required: - url - method - priceUsdc properties: url: type: string description: Normalized target URL (fragment removed). method: $ref: '#/components/schemas/HttpMethod' priceUsdc: type: string pattern: ^[0-9]+\.[0-9]{2,6}$ description: Price the target asked for in its 402 challenge. estimatedMaxSpendUsdc: type: string pattern: ^[0-9]+\.[0-9]{2,6}$ description: >- What Selo expects to pay the target: one paid request at the target's price. seloPriceUsdc: type: string pattern: ^[0-9]+\.[0-9]{2,6}$ description: What the release test costs you, paid to Selo over x402. expiresAt: type: string format: date-time description: The preflight is valid for 15 minutes. PreflightIneligible: type: object description: The target cannot be tested. Nothing was paid. required: - eligible - preflightId - reason - message properties: eligible: type: boolean const: false preflightId: type: - string - 'null' description: >- ID of the stored preflight, or `null` when Selo refused the request before storing it (invalid URL, blocked hostname, unknown authorization). reason: $ref: '#/components/schemas/PreflightRejection' message: type: string HttpMethod: type: string enum: - GET - POST description: HTTP method Selo uses to call the target. PreflightRejection: type: string enum: - AUTHORIZATION_MISSING - AUTHORIZATION_EXPIRED - TARGET_URL_INVALID - TARGET_NOT_HTTPS - TARGET_ADDRESS_BLOCKED - METHOD_NOT_ALLOWED - TARGET_UNREACHABLE - NO_PAYMENT_CHALLENGE - NETWORK_NOT_SUPPORTED - ASSET_NOT_SUPPORTED - PRICE_OVER_BUDGET description: Why a target is not eligible for a release test. responses: InternalError: description: Unexpected server error. content: application/json: schema: $ref: '#/components/schemas/ApiError' examples: INTERNAL: summary: Unexpected server error value: error: INTERNAL message: Internal server error ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.