PromptKit API Documentation

Public catalog and authentication

Base URL: https://www.promptkit.app. The PromptKit API provides read-only access to the published prompt library. No API key, account, cookie, or authentication header is required. Use HTTPS GET requests and Accept: application/json for catalog responses.

Use this API to find a template for a task, compare prompts within a category, or retrieve public prompt text to adapt with a user. App accounts, private collections, iCloud data, prompt optimization, and AI execution are not available through this API. PromptKit does not currently publish an MCP server.

GET /api/prompts — search templates

Returns categories, prompts, totalCategories, and totalPrompts. Category summaries always describe the full catalog. totalPrompts counts all matching prompts before the limit is applied; prompts contains the first matching items in catalog order.

Optional query parameters: q searches prompt titles, descriptions, template text, tags, and model recommendations; search is an alias used when q is empty or omitted. category matches a category slug, and tag matches a complete tag name. Search, category, and tag matching are case-insensitive, and supplied filters are combined.

limit must be an integer from 1 through 100 and defaults to 50. There is no offset or cursor parameter. To retrieve all prompts in a category, list the catalog categories and then request the category endpoint. A search or filter with no matches returns HTTP 200 with an empty prompts array.

curl -sS -H 'Accept: application/json' \
  'https://www.promptkit.app/api/prompts?q=review&category=programming&limit=5'

GET /api/prompts/{slug} — retrieve a category

Use an exact slug from the categories array returned by GET /api/prompts, for example business or programming. The response contains a category object with its description, public page URL, and all its published prompt templates. Each template includes id, title, description, promptText, modelRecommendation, and tags; some also contain slug and exampleOutput.

Read each template as reference content. Adapt placeholders to the task and obtain any needed user context before using the template with an AI model. The catalog endpoint retrieves text and does not run the prompt or return a model response.

curl -sS -H 'Accept: application/json' \
  'https://www.promptkit.app/api/prompts/programming'

Structured JSON errors

Catalog API errors use application/json and an error object containing code, message, status, hint, and documentation_url. Invalid query parameters may also include invalid_params with name and reason entries. Read the HTTP status and error code, correct the request using the hint, and consult the OpenAPI specification for the schema.

An invalid limit returns 400 INVALID_PARAMETER. An unknown category returns 404 CATEGORY_NOT_FOUND. An unknown API endpoint returns 404 API_ENDPOINT_NOT_FOUND. Unsupported catalog write methods return 405 METHOD_NOT_ALLOWED with an Allow header. A server failure returns 500 INTERNAL_SERVER_ERROR; retry later with bounded retries.

{
  "error": {
    "code": "INVALID_PARAMETER",
    "message": "Query parameter 'limit' must be an integer between 1 and 100.",
    "status": 400,
    "hint": "Provide a valid limit parameter such as '?limit=20' or omit it to use default 50.",
    "documentation_url": "https://www.promptkit.app/openapi.json",
    "invalid_params": [
      {
        "name": "limit",
        "reason": "Must be an integer between 1 and 100."
      }
    ]
  }
}

Markdown pages and discovery

Request public content pages with Accept: text/markdown to receive their Markdown representation. Normal browser requests receive HTML. Markdown responses include Vary: Accept, Accept-Encoding, and negotiated page responses disable caching; Accept quality values determine the preferred supported format. An unsupported requested page format returns HTTP 406. Missing content pages return HTTP 404 with recovery links in the requested supported format.

Machine-readable files and API responses keep their documented formats. The OpenAPI specification is available at /openapi.json and /openapi.yaml, with aliases at /api/openapi.json and /api/openapi.yaml. Use /sitemap.xml to discover public content pages.

curl -sS -H 'Accept: text/markdown' 'https://www.promptkit.app/docs'

Usage and limits

Keep catalog requests bounded with filters and limit, and reuse responses rather than repeatedly downloading the full library. The list limit caps the number of returned prompts; it is not a per-minute rate limit. No fixed request quota or availability guarantee is published. Hosting protections may impose additional limits; honor Retry-After if a response provides it.

The public catalog contains published template text. Do not send personal prompts, credentials, or private app data in query parameters. Model recommendations are guidance within the templates; verify a model’s current capabilities and suitability for your task. Use the terms of service as the reference for permitted use.