API

The systemprompt.io API gives you programmatic access to the platform. You can create and manage skills, configure agents, install plugins, and publish content -- all through standard REST calls.

Base URL

All API requests use the following base URL:

https://systemprompt.io/api/v1/

Every endpoint path documented in this reference is relative to that base. For example, the skills list endpoint is:

GET https://systemprompt.io/api/v1/skills

REST Conventions

The API follows standard REST conventions:

Method	Purpose
GET	Retrieve a resource or list of resources
POST	Create a new resource
PUT	Replace a resource entirely
PATCH	Update specific fields on a resource
DELETE	Remove a resource

All endpoints accept and return JSON. Set the Content-Type header to application/json on requests that include a body.

Request Format

Include your API key in every request using the Authorization header. Request bodies should be valid JSON.

curl -X POST https://systemprompt.io/api/v1/skills \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "My Skill",
    "description": "A skill that does something useful"
  }'

Response Format

Responses return JSON with a consistent structure. Successful responses include the requested data directly:

{
  "id": "sk_abc123",
  "name": "My Skill",
  "description": "A skill that does something useful",
  "created_at": "2026-02-24T12:00:00Z",
  "updated_at": "2026-02-24T12:00:00Z"
}

List endpoints return an array of items along with pagination metadata:

{
  "items": [ ... ],
  "total": 42,
  "page": 1,
  "per_page": 20
}

Error Format

When a request fails, the API returns an error object with a machine-readable code and a human-readable message:

{
  "error": {
    "code": "validation_error",
    "message": "The 'name' field is required.",
    "status": 422
  }
}

Common error codes:

Status	Code	Meaning
400	bad_request	The request body is malformed or missing required fields
401	unauthorized	Missing or invalid API key
403	forbidden	Your API key does not have permission for this action
404	not_found	The requested resource does not exist
422	validation_error	The request is well-formed but contains invalid values
429	rate_limited	Too many requests -- slow down and retry
500	internal_error	Something went wrong on our end

Rate Limits

The API enforces rate limits to ensure fair usage. The current limits are:

• 100 requests per minute per API key for standard plans
• 500 requests per minute per API key for professional plans

Rate limit headers are included in every response:

Header	Description
X-RateLimit-Limit	Maximum requests allowed per window
X-RateLimit-Remaining	Requests remaining in the current window
X-RateLimit-Reset	Unix timestamp when the window resets

When you hit the rate limit, the API returns a 429 status. Wait until the reset time before retrying.

Getting Started

Follow these steps to make your first API call:

1. Sign in to the dashboard. Go to systemprompt.io and log in to your account.

2. Generate an API key. Navigate to Settings, then API Keys. Click "Create API Key" and give it a descriptive name. Copy the key immediately -- it will not be shown again. See the Authentication page for full details.

3. Make a test request. Verify your key works by listing your skills:

curl https://systemprompt.io/api/v1/skills \
  -H "Authorization: Bearer YOUR_API_KEY"

4. Check the response. You should receive a JSON response with your skills list. If you get a 401 error, double-check your API key.

5. Explore the endpoints. Browse the API Endpoints reference to find the operations you need.

Pagination

List endpoints support pagination through query parameters:

Parameter	Default	Description
page	1	Page number to retrieve
per_page	20	Number of items per page (max 100)

Example:

curl "https://systemprompt.io/api/v1/skills?page=2&per_page=50" \
  -H "Authorization: Bearer YOUR_API_KEY"

Next Steps

• API Authentication -- Learn how to generate keys, manage scopes, and secure your API access.
• API Endpoints -- Browse the complete endpoint reference with examples for skills, agents, plugins, and more.