# Bastion Helix Agent Lens API

> Web pages for AI agents. Find out what a site offers agents and whether a page may be used, then read it as clean Markdown, get its published facts as JSON, re-check it for only what changed, list its forms and buttons with selectors, or screenshot it. Paid calls are charged only when they succeed. Not affiliated with Cloudflare; uses Cloudflare Browser Run (Kitesurf and Chromium) on Bastion Helix's own account.

## Endpoints (POST JSON {"url": "https://..."})
- https://lens.bastionhelix.com/v1/preflight: free, rate-limited. Robots.txt and Content Signals for this service (and your bot if you pass "user_agent"), bot checks, sign-in walls, and which engine each task needs (fetch, kitesurf, chromium, blocked).
- https://lens.bastionhelix.com/v1/site: free, rate-limited. A site card: llms.txt, sitemap, feeds, Content Signals, and which known AI crawlers/agents robots.txt allows.
- https://lens.bastionhelix.com/v1/read: US$0.004. Clean Markdown. Options: engine (auto|fetch|kitesurf|chromium), max_chars.
- https://lens.bastionhelix.com/v1/actions: US$0.004. Forms with fields, buttons, links, each with a CSS selector.
- https://lens.bastionhelix.com/v1/extract: US$0.002. Facts the page publishes, no AI model: JSON-LD/schema.org, offers and prices, meta/Open Graph, canonical, feeds, HTML tables.
- https://lens.bastionhelix.com/v1/delta: US$0.001. Only what changed since your last check. First call returns sections + "fingerprint"; send it back as "previous". Uses ETag/Last-Modified when available. Nothing stored on our side.
- https://lens.bastionhelix.com/v1/screenshot: US$0.008. PNG (send Accept: image/png) or JSON with image_base64. Options: engine (auto|kitesurf|chromium), full_page.
- GET https://lens.bastionhelix.com/v1/credits: credits left on your API key.

## MCP
- https://lens.bastionhelix.com/mcp (Streamable HTTP). Tools: preflight, site, read, extract, delta, actions, screenshot, credits.

## Paying
- API key with prepaid credits (1 credit = US$0.001): header Authorization: Bearer bhk_... Buy at https://bastionhelix.com/lens#pricing
- x402: coming soon.

## Rules this service keeps
- It obeys robots.txt for "BastionHelixAgentLens" and, when you pass user_agent, for your bot too.
- It refuses pages whose Content Signals say ai-input=no.
- It never tries to get past bot checks or human checks, and never signs in.
- Refusals and failures are never charged.

## More
- OpenAPI: https://lens.bastionhelix.com/openapi.json
- Docs: https://bastionhelix.com/lens/docs
- Privacy: https://bastionhelix.com/lens/privacy