> ## Documentation Index
> Fetch the complete documentation index at: https://socialintel.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# FAQ

> Frequently asked questions about the Social Intel API.

<AccordionGroup>
  <Accordion title="Do I need an API key?">
    No. Social Intel API uses the x402 protocol, where payment is authentication. Any wallet with USDC on Base or Solana can use the API immediately — no signup, no API keys, no OAuth.
  </Accordion>

  <Accordion title="What chains are supported for payment?">
    USDC on **Base** and **Solana**. Both are mainnet. Base is recommended for lowest gas fees.
  </Accordion>

  <Accordion title="Why does the API return HTTP 402?">
    HTTP 402 ("Payment Required") is part of the x402 protocol. When you send a request, the API responds with 402 and includes payment details (amount, wallet address, chain) in the response headers. Your x402 client library handles the payment automatically and retries the request — you get results without any extra code.
  </Accordion>

  <Accordion title="What is x402?">
    [x402](https://www.x402.org/) is an open protocol for pay-per-request APIs using stablecoins. It uses the HTTP 402 status code to negotiate payments. Client libraries handle the payment flow automatically, making it transparent to developers.
  </Accordion>

  <Accordion title="How much does it cost?">
    $0.10 for up to 20 results. Each additional result above 20 costs $0.002, up to a maximum of 100 results (\$0.26). See [Pricing](/docs/reference/pricing) for the full formula and cost optimization tips.
  </Accordion>

  <Accordion title="Are there rate limits?">
    There are no per-key rate limits since there are no API keys. However, there are general rate limits to prevent abuse. If you hit a rate limit, you'll receive HTTP 429 with a `Retry-After` header.
  </Accordion>

  <Accordion title="Can I use this with Claude Desktop or Cursor?">
    Yes. Social Intel API has an MCP server that works with Claude Desktop, Cursor, Windsurf, and any MCP-compatible client. See [MCP Integration](/docs/guides/mcp-integration) for setup instructions.
  </Accordion>

  <Accordion title="What data is returned per influencer?">
    Each result includes: `username`, `full_name`, `followers`, `following`, `category`, `bio`, `public_email`, `is_verified`, and `is_business`. See [Response Schema](/docs/reference/response-schema) for details on every field.
  </Accordion>

  <Accordion title="Do all results have email addresses?">
    No. Only business/creator accounts with a public email set will have the `public_email` field. Typically 15-25% of results include an email. Use `category` filters to increase the business account ratio.
  </Accordion>

  <Accordion title="What is the data source?">
    Social Intel API aggregates publicly available Instagram profile data. All data is sourced from public profiles — no scraping of private accounts or DMs.
  </Accordion>

  <Accordion title="Can I filter by follower range?">
    Yes. Use `min_followers` and `max_followers` parameters. For example, `min_followers=10000&max_followers=100000` finds micro-influencers with 10K-100K followers.
  </Accordion>

  <Accordion title="What countries are supported?">
    Most countries with significant Instagram usage. Use standard ISO 3166-1 alpha-2 country codes (US, UK, DE, FR, etc.). See [Parameters](/docs/reference/parameters) for a full list.
  </Accordion>
</AccordionGroup>