> ## Documentation Index > Fetch the complete documentation index at: https://iotools.cloud/docs/llms.txt > Use this file to discover all available pages before exploring further. # Get credit usage history > What the key's owner spent credits on, over the last 30 days — one row per tool per day per surface (`web`, `api`, `mcp`), newest and biggest first. Free: this call costs no credits. A usage history, not a ledger: rows only exist for days with spend, and `credits` is net of any settlement refund. ## OpenAPI ````yaml https://api.iotools.cloud/v1/openapi get /v1/me/usage openapi: 3.1.0 info: title: iotools.cloud API version: 1.0.0 description: >- Run any iotools.cloud tool over HTTP. Authenticate with `Authorization: Bearer iot_live_…`. **Only `POST /v1/tool/{slug}` costs credits.** Every GET here — the catalog, a tool's schema, your balance — is free. A tool call is charged its own weight or your plan's per-call minimum, whichever is larger; `x-iotools-credit-cost` on each operation is quoted at the free-tier minimum, and `GET /v1/tools/list` returns the exact figure for your key. `GET /v1/me/credits` reports what you have left, and `GET /v1/me/usage` reports what it went on. Failures are RFC 9457 problem documents — branch on `code`. servers: - url: https://api.iotools.cloud description: Production security: - bearerAuth: [] tags: - name: Catalog description: Find a tool and read its contract. Free. - name: Converters description: >- Convert between formats, encodings, and units — Base64, CSV and JSON, timestamps, and more. Fast, free, and processed right in your browser. - name: Formatters description: >- Format, beautify, minify, and validate code and data — JSON, HTML, CSS, SQL, and regex. Clean up messy input in one click, with nothing to upload. - name: Generators description: >- Generate exactly what you need and on demand — passwords, UUIDs, QR codes, hashes, random numbers, and more. Secure, instant, and free. - name: Calculators description: >- Crunch the numbers fast — from everyday math to specialized conversions and unit work. Free online calculators that run entirely in your browser. - name: Editors description: >- Edit and transform text, code, and images with quick, focused editors that run entirely in your browser — nothing to install, and no sign-up needed. - name: Utilities description: >- Everyday developer and web utilities — DNS and IP lookups, redirect and certificate checkers, and other quick diagnostics. Free and privacy-friendly. - name: Account description: Your key's allowance, limits and usage history. paths: /v1/me/usage: get: tags: - Account summary: Get credit usage history description: >- What the key's owner spent credits on, over the last 30 days — one row per tool per day per surface (`web`, `api`, `mcp`), newest and biggest first. Free: this call costs no credits. A usage history, not a ledger: rows only exist for days with spend, and `credits` is net of any settlement refund. operationId: get_usage responses: '200': description: The key owner's recent spend. content: application/json: schema: type: object required: - days - items properties: days: type: integer description: How many days of history this response covers. items: type: array items: type: object required: - day - slug - title - surface - credits - runs properties: day: type: string format: date description: UTC, `YYYY-MM-DD`. slug: type: string title: type: string surface: type: string description: Where the spend happened, e.g. `web`, `api`, `mcp`. credits: type: integer runs: type: integer example: days: 30 items: - day: '2026-07-28' slug: ai-writer title: AI Writer surface: api credits: 24 runs: 1 - day: '2026-07-27' slug: case-converter title: String Case Converter surface: mcp credits: 3 runs: 1 '401': description: Missing or invalid API key. content: application/problem+json: schema: $ref: '#/components/schemas/Problem' example: type: https://iotools.cloud/docs/errors/invalid_api_key title: Invalid API key status: 401 code: invalid_api_key detail: 'Provide ''Authorization: Bearer ''.' request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 '429': description: Rate limited. content: application/problem+json: schema: $ref: '#/components/schemas/Problem' example: type: https://iotools.cloud/docs/errors/rate_limited title: Rate limit exceeded status: 429 code: rate_limited detail: Too many requests. Retry in 30s. request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11 security: - bearerAuth: [] components: schemas: Problem: type: object description: >- RFC 9457 problem document, served as application/problem+json. Branch on `code`; `title` is human prose and may be reworded without notice. required: - type - title - status - code properties: type: type: string format: uri description: Stable documentation URI for this failure. examples: - https://iotools.cloud/docs/errors/invalid_api_key - https://iotools.cloud/docs/errors/api_unconfigured - https://iotools.cloud/docs/errors/validation_error - https://iotools.cloud/docs/errors/payload_too_large - https://iotools.cloud/docs/errors/tool_not_found - https://iotools.cloud/docs/errors/tool_not_allowed - https://iotools.cloud/docs/errors/tool_disabled - https://iotools.cloud/docs/errors/rate_limited - https://iotools.cloud/docs/errors/insufficient_credits - https://iotools.cloud/docs/errors/processing_error - https://iotools.cloud/docs/errors/internal_error title: type: string examples: - Invalid API key - API not configured - Invalid request - Payload too large - Tool not found - Tool not available over the API - Tool temporarily disabled - Rate limit exceeded - Insufficient credits - Tool failed to run - Internal error status: type: integer code: type: string enum: - invalid_api_key - api_unconfigured - validation_error - payload_too_large - tool_not_found - tool_not_allowed - tool_disabled - rate_limited - insufficient_credits - processing_error - internal_error detail: type: string description: Human explanation of this occurrence. request_id: type: string description: Correlation id, also sent as x-request-id. securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: iot_live_… ````