> ## Documentation Index > Fetch the complete documentation index at: https://docs.tradingapi.dev/llms.txt > Use this file to discover all available pages before exploring further. # Get the calling key > Returns the limits of the API key making the request, and how much of its daily limit is used. Call it first to find out what the key may do. Limits are set on the account page, never through the API. ## OpenAPI ````yaml /openapi.yaml get /v1/api_key openapi: 3.1.0 info: title: Trading API license: name: Proprietary identifier: LicenseRef-Proprietary version: '1' summary: Trade perpetual futures on Hyperliquid with plain HTTP requests. description: > The Trading API places market orders on Hyperliquid perpetual futures and reports your positions, fills and balance. You never sign anything, manage nonces or look up asset indexes: send a market, a side and a value in US dollars. Every request authenticates with an API key created on the account page: `Authorization: Bearer tapi_…`. servers: - url: https://tradingapi.dev description: Production. Orders trade real money on Hyperliquid mainnet. security: - apiKey: [] tags: - name: Markets description: The markets you can trade, with their rules and current prices. - name: Orders description: Place, preview, list and look up orders. - name: Positions description: Your open positions, and closing them. - name: Account description: Your balance, the calling key, fills and withdrawals. paths: /v1/api_key: get: tags: - Account summary: Get the calling key description: > Returns the limits of the API key making the request, and how much of its daily limit is used. Call it first to find out what the key may do. Limits are set on the account page, never through the API. operationId: getApiKey responses: '200': description: The calling key. content: application/json: schema: $ref: '#/components/schemas/ApiKey' examples: key: value: object: api_key name: research-agent limits: markets: - BTC - ETH - SOL max_order_value: '250.00' max_daily_value: '1000.00' usage: daily_value_used: '842.60' daily_value_remaining: '157.40' next_release: at: '2026-09-27T18:02:40.000Z' value: '250.00' '401': $ref: '#/components/responses/Unauthorized' '429': $ref: '#/components/responses/RateLimited' components: schemas: ApiKey: type: object required: - object - name - limits - usage properties: object: type: string const: api_key name: type: string limits: type: - object - 'null' description: >- `null` for a key without limits, which cannot trade until they are set. properties: markets: type: array items: type: string max_order_value: type: string max_daily_value: type: string usage: type: object properties: daily_value_used: type: string description: >- The value of orders this key placed in the last 24 hours. Reduce-only orders and closes don't count. daily_value_remaining: type: string next_release: type: - object - 'null' description: >- When the oldest usage leaves the 24-hour window, and how much it frees. properties: at: $ref: '#/components/schemas/Timestamp' value: type: string Timestamp: type: string format: date-time description: >- RFC 3339 in UTC with milliseconds, for example `2026-09-27T14:30:00.123Z`. ErrorResponse: type: object required: - error properties: error: $ref: '#/components/schemas/Error' Error: type: object required: - type - code - message - param - hint - details - errors - retryable - doc_url properties: type: type: string enum: - invalid_request - authentication - permission - not_found - conflict - unprocessable - rate_limited - unavailable - internal description: The kind of error. It determines the HTTP status. code: type: string description: >- A stable identifier for the error. Branch on this. New codes may be added. message: type: string description: What was wrong, with the values involved. param: type: - string - 'null' description: The request field at fault, as a JSON path, or `null`. hint: type: - string - 'null' description: One concrete way to fix the request. details: type: object description: The numbers and values the message refers to, as fields. additionalProperties: true errors: type: array description: Every field error, when `code` is `invalid_fields`. Empty otherwise. items: $ref: '#/components/schemas/Error' retryable: type: boolean description: Whether the same request can succeed later, unchanged. retry_after: $ref: '#/components/schemas/Timestamp' description: When a retry can succeed, if known. doc_url: type: string format: uri responses: Unauthorized: description: No valid API key. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: invalid_api_key: value: error: type: authentication code: invalid_api_key message: This API key is not valid. It may have been revoked. param: null hint: >- Send a current key as Authorization: Bearer tapi_…. Keys are created and revoked on the account page. details: {} errors: [] retryable: false doc_url: >- https://docs.tradingapi.dev/api-reference/errors#invalid_api_key RateLimited: description: >- The key made too many requests. Each key may make 10 requests at once, then 5 a second. Nothing was done; retry after `Retry-After` seconds. headers: Retry-After: description: The seconds to wait before retrying, always `1`. schema: type: string enum: - '1' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: rate_limited: value: error: type: rate_limited code: rate_limited message: This key made too many requests; retry in 1 s. param: null hint: >- Slow down: each key may make 10 requests at once, then 5 a second. details: {} errors: [] retryable: true retry_after: '2026-09-28T14:05:12.000Z' doc_url: >- https://docs.tradingapi.dev/api-reference/errors#rate_limited securitySchemes: apiKey: type: http scheme: bearer bearerFormat: tapi_… description: >- An API key from the account page, sent as `Authorization: Bearer tapi_…`. ````