> ## Documentation Index > Fetch the complete documentation index at: https://crushrewards.dev/docs/llms.txt > Use this file to discover all available pages before exploring further. # GS1 GPC attribute schema for one or more bricks > Return the GPC attribute schema for one or more bricks - attribute names and their allowed value sets. Accepts up to 100 comma-separated gpc_code values. Use this to discover which attributes GS1 defines for a product category (for example Formation, If Organic) and the controlled vocabulary each one permits. Bricks that define no attributes return an empty attributes array. ## OpenAPI ````yaml https://api.syntalic.com/openapi.json get /v1/reference/brick-attributes openapi: 3.1.0 info: title: 'Syntalic — Data Analytics for Agentic Commerce ' version: 1.0.0 description: >- Competitive pricing data across US and Canadian e-commerce retailers (Amazon, Walmart, Target, Best Buy, Home Depot, etc.). Serves price comparisons, deal alerts, brand tracking, promotional intelligence, and market analytics to AI agents via x402 and MPP micropayments. x-guidance: >- This API has three endpoint groups organized by use case: **Shopper endpoints** ($0.01/query): Use these for price comparisons and deal hunting. Start with /v1/shopper/best-price?q= to find the cheapest option across retailers. Use /v1/shopper/deal-finder?category= to find discounted products. Use /v1/shopper/price-drop-alert?q= to check for recent price drops. **Marketing endpoints** ($0.01/query): Use these for competitive analysis. /v1/marketing/competitive-landscape?category= shows all products in a category with pricing. /v1/marketing/brand-tracker?brand= tracks a brand's pricing over time. /v1/marketing/share-of-shelf?category= shows brand market share. **Analyst endpoints** ($0.02/query): Use these for market-level insights. /v1/analyst/inflation?category= shows price trends over time. /v1/analyst/price-dispersion?category= shows price spread across retailers. All endpoints accept an optional 'country' parameter (us or ca, defaults to us). Query parameters use 'q' for free-text search and 'category' for category-level queries. Marketing and analyst responses carry a `meta` block (served_from, freshness_seconds, schema_version) for staleness budgeting and a `resolved` block describing how the category input was matched against the taxonomy. Every response also sends an X-Data-Freshness-Hours header. **Free pre-payment rejection:** requests that cannot be served are rejected BEFORE any payment challenge — invalid params (400 INVALID_PARAMS), retailers that are not serving-eligible (404 RETAILER_NOT_SERVING_ELIGIBLE, with the catalog quality status and the serving_eligible_retailers list in error.details), and shopper queries that resolve to nothing in the catalog (404 NO_RESULTS). You only pay when the API can actually execute your query. Retailer values are case-insensitive (amazon == Amazon). servers: - url: https://api.syntalic.com security: [] paths: /v1/reference/brick-attributes: get: tags: - Reference summary: GS1 GPC attribute schema for one or more bricks description: >- Return the GPC attribute schema for one or more bricks - attribute names and their allowed value sets. Accepts up to 100 comma-separated gpc_code values. Use this to discover which attributes GS1 defines for a product category (for example Formation, If Organic) and the controlled vocabulary each one permits. Bricks that define no attributes return an empty attributes array. operationId: getGpcBrickAttributes parameters: - name: gpc_code in: query required: true schema: type: string pattern: ^\d{8}(,\d{8})*$ description: Comma-separated 8-digit GS1 GPC brick codes (max 100 per request) example: '10000002' responses: '200': description: GPC brick attribute schemas content: application/json: schema: type: object properties: results: type: array items: type: object properties: gpc_code: type: string gpc: type: object nullable: true description: >- The matched GS1 GPC node and its ancestry. null when the id has no mapping. properties: code: type: string title: type: string level: type: string enum: - brick - class - family - segment segment: type: string nullable: true family: type: string nullable: true class: type: string nullable: true brick: type: string nullable: true attributes: type: array items: type: object properties: name: type: string allowed_values: type: array items: type: string value_count: type: integer gpc_release: type: string example: v20260520 schema_version: type: string example: v3 '400': description: >- Invalid query parameters or unsupported enum values. Rejected by preflight BEFORE the payment challenge — no payment is requested or charged for malformed requests. content: application/problem+json: schema: type: object required: - type - title - status properties: type: type: string format: uri-reference title: type: string example: Bad Request status: type: integer const: 400 detail: type: string instance: type: string error: type: object properties: code: type: string message: type: string details: type: object additionalProperties: true additionalProperties: true additionalProperties: true '402': description: Payment challenge required before executing paid work content: application/problem+json: schema: type: object required: - type - title - status properties: type: type: string format: uri-reference title: type: string example: Payment Required status: type: integer const: 402 detail: type: string instance: type: string error: type: object properties: code: type: string message: type: string details: type: object additionalProperties: true additionalProperties: true additionalProperties: true '404': description: >- No matching result. error.code distinguishes the cases: NO_RESULTS (the query resolves to nothing in the catalog) or RETAILER_NOT_SERVING_ELIGIBLE (the requested retailer exists but is not serving-eligible — error.details carries its catalog quality_status and the serving_eligible_retailers list to retry against). Structurally-unservable requests are rejected by preflight before any payment challenge. content: application/problem+json: schema: type: object required: - type - title - status properties: type: type: string format: uri-reference title: type: string example: Not Found status: type: integer const: 404 detail: type: string instance: type: string error: type: object properties: code: type: string message: type: string details: type: object additionalProperties: true additionalProperties: true additionalProperties: true '429': description: Rate limit exceeded content: application/problem+json: schema: type: object required: - type - title - status properties: type: type: string format: uri-reference title: type: string example: Too Many Requests status: type: integer const: 429 detail: type: string instance: type: string error: type: object properties: code: type: string message: type: string details: type: object additionalProperties: true additionalProperties: true additionalProperties: true '500': description: Unexpected server error content: application/problem+json: schema: type: object required: - type - title - status properties: type: type: string format: uri-reference title: type: string example: Internal Server Error status: type: integer const: 500 detail: type: string instance: type: string error: type: object properties: code: type: string message: type: string details: type: object additionalProperties: true additionalProperties: true additionalProperties: true ````