> ## Documentation Index > Fetch the complete documentation index at: https://docs.kairos.trade/llms.txt > Use this file to discover all available pages before exploring further. # Trending market ids for a live-price subscription > Same ranking as `/api/markets/trending`, reduced to the fields a WebSocket subscriber needs to open a live-price stream (id, symbol, price, 24h volume). Not cached — every call reads the trending index directly. ## OpenAPI ````yaml /openapi/data-api.yaml get /api/markets/trending/ws openapi: 3.1.0 info: title: Kairos Data API version: 1.0.0 summary: >- The full Kairos data plane — markets, candles, trades, search, discover, sports, trader analytics, and PnL. description: | The Kairos Data API at `data.kairos.trade` is the platform's primary data plane: market metadata and prices, OHLCV candles, live venue trade proxies, normalized trade history, full-text search, discovery feeds, the sports catalog, public trader analytics, and account PnL. ## Authentication Most endpoints accept a Kairos **API key** (`X-Client-Id` + `X-Api-Key` + `X-Api-Secret`, all three) or a first-party session JWT. Endpoints tagged `public` (trader analytics, provider configs, several sports feeds) need no credentials at all. Some endpoints additionally require an API-key **scope** (`trade:read`, `position:read`) — stated per operation. For high-volume market-data consumption (candles/trades/metadata at scale), prefer the dedicated **Market Data API** at `md.kairos.trade` — it has higher budgets, ETag caching, and a binary candle format. ## Rate limits Rate limits use a sliding window keyed on the authenticated user (JWT `sub`) or, for anonymous callers, the trusted client IP. Routes belong to a named **bucket** (`x-kairos-bucket`) whose per-minute budget is shared by every route in it; routes with no bucket run under the service default of 100/minute. `x-kairos-rate-limit` states the bucket's compile-time default — operators can raise or lower a bucket at runtime, so treat the documented number as the baseline, not a contract. 429 responses carry `Retry-After` and `X-RateLimit-*`. ## Conventions - Prices are on the **0–100 cents scale** unless a field says otherwise (trader-analytics position/trade prices use the 0–1 scale; each field's description states its scale). - Errors: `{"detail": ""}` for handler errors; FastAPI's standard validation envelope for 422s. Errors surfaced from a venue adapter instead use `{"error", "provider", "operation", "message"}` — see `DataProviderError`. Unhandled failures always return the generic 500 body; internal details are logged, never returned. - Every request body is capped at 8 MiB service-wide (413). contact: name: Kairos url: https://app.kairos.trade/docs/api-reference termsOfService: https://kairos.trade/terms servers: - url: https://data.kairos.trade description: Production - url: https://staging-data.kairos.trade description: Staging security: - apiKeyClientId: [] apiKeyKey: [] apiKeySecret: [] paths: /api/markets/trending/ws: get: tags: - Discover summary: Trending market ids for a live-price subscription description: >- Same ranking as `/api/markets/trending`, reduced to the fields a WebSocket subscriber needs to open a live-price stream (id, symbol, price, 24h volume). Not cached — every call reads the trending index directly. operationId: discoverTrendingMarketIds parameters: - name: limit in: query schema: type: integer minimum: 1 maximum: 300 default: 20 - name: provider in: query description: Provider id filter, or omit for every provider. schema: type: string responses: '200': description: Trending market ids ranked by 1h volume. content: application/json: schema: $ref: '#/components/schemas/DiscoverTrendingWsResponse' '401': $ref: '#/components/responses/DataUnauthorized' '403': $ref: '#/components/responses/DataForbidden' '422': $ref: '#/components/responses/DataValidationError' '429': $ref: '#/components/responses/DataRateLimited' '500': description: Trending lookup failed. content: application/json: schema: $ref: '#/components/schemas/DataError' components: schemas: DiscoverTrendingWsResponse: type: object required: - markets - count - timestamp properties: markets: type: array items: $ref: '#/components/schemas/DiscoverTrendingWsMarket' count: type: integer timestamp: type: string DataError: type: object description: Handler error envelope (FastAPI HTTPException). required: - detail properties: detail: type: string description: Human-readable error message. example: Invalid provider DiscoverTrendingWsMarket: type: object description: Trending market reduced to what a live-price subscriber needs. properties: id: type: string symbol: type: - string - 'null' title: type: string price: type: number volume24h: type: number provider: type: string responses: DataUnauthorized: description: > No valid credential presented — missing/invalid API-key headers, or an invalid/expired session token. content: application/json: schema: $ref: '#/components/schemas/DataError' example: detail: Not authenticated DataForbidden: description: > Authenticated but not permitted. Three distinct causes: the session user is not invited (`Invite required`), the API key lacks the operation's scope, or API-key access to the requested venue is switched off (`API access is disabled for `). Admin and API-key callers bypass the invite check; session and admin callers bypass scope and venue checks. content: application/json: schema: $ref: '#/components/schemas/DataError' example: detail: Invite required DataValidationError: description: Request failed FastAPI parameter validation. content: application/json: schema: type: object required: - detail properties: detail: type: array description: >- One entry per failed field, with location, message, and error type. items: type: object additionalProperties: true DataRateLimited: description: > Rate limit exceeded for this route's sliding window, keyed on the session `sub` when authenticated and on the trusted client IP otherwise. Honor `Retry-After`. A per-API-key data ceiling (set per credential) rejects with `{"detail": "API key data rate limit exceeded"}` instead of the `error` envelope below. headers: Retry-After: schema: type: integer X-RateLimit-Limit: schema: type: integer X-RateLimit-Remaining: schema: type: integer X-RateLimit-Reset: schema: type: integer content: application/json: schema: type: object properties: error: type: string example: 'Rate limit exceeded: 100 per 1 minute' securitySchemes: apiKeyClientId: type: apiKey in: header name: X-Client-Id description: >- Credential client id (`kairos_ck_...`). Must be sent together with X-Api-Key and X-Api-Secret. apiKeyKey: type: apiKey in: header name: X-Api-Key description: 64-char hex API key. apiKeySecret: type: apiKey in: header name: X-Api-Secret description: 64-char hex API secret. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.