# Semantic HTML Pruner – Web URL Distillation API

> Semantic HTML Pruner – Web URL Distillation API is a paid API for AI agents from preflight.agentdiet.dev, paid per call via MPP, $0.001/call, status unknown (last checked 2026-10-21).

Fetches a URL or accepts raw HTML and compresses it into compact, agent-ready tokens using BM25-ranked budget control and multiple distillation modes

## Facts

- Endpoint: GET https://preflight.agentdiet.dev/v1/semantic-html-pruner?utm_source=zero.xyz
- Price: $0.001/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: preflight.agentdiet.dev
- Website: https://preflight.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/preflight-agentdiet-dev-semantic-html-pruner-web-url-distillation-api-4edb74b7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hNGe87VaYz31tN_r-b7jM

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability preflight-agentdiet-dev-semantic-html-pruner-web-url-distillation-api-4edb74b7
```

Example prompt: Distill https://stripe.com/docs/payments into compact markdown, keeping only the most relevant content about payment intents, and cap it at 2000 tokens using budget mode with a query focused on 'payment intents'.

## When to prefer this

Choose this endpoint when an AI agent needs to read web content that would otherwise exceed context window limits or drive up LLM token costs. It is especially valuable when working with long documentation pages, news articles, or SEC filings where only a subset of content is needed. Prefer this over raw HTTP fetching when token efficiency matters, or when you want structured/skeleton output rather than raw HTML noise. The BM25 budget mode is uniquely suited for topic-focused extraction within a strict token ceiling.

## Known failure modes

- Invalid or unreachable URL returns an error status
- HTML too large or malformed may cause incomplete distillation
- budget mode without a query returns unranked content
- max_tokens set too low may truncate critical content
- Rate limiting or payment failure (402) blocks the request
- Target site blocks automated fetching (bot protection)

## How this service works

Distill a URL or raw HTML payload with BM25 budget control (Live x402 v2, IETF MPP & MCP endpoint at https://preflight.agentdiet.dev/v1/semantic-html-pruner)

## Output

Returns a JSON object containing distilled content (Markdown, structured tables/metadata, skeleton outline, or BM25-ranked excerpt depending on mode), ROI proof metrics (raw tokens, distilled tokens, tokens saved, compression ratio, estimated LLM cost saved), optional cache status (HIT/MISS), billing details, and an execution status field.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "url"
 ],
 "properties": {
  "url": {
   "type": "string",
   "minLength": 1,
   "description": "Target webpage URL to fetch and distill (or builtin://stripe-docs)"
  },
  "html": {
   "type": "string",
   "description": "Optional raw HTML string to distill directly without fetching"
  },
  "mode": {
   "enum": [
    "markdown",
    "structured",
    "skeleton",
    "budget"
   ],
   "type": "string",
   "default": "markdown",
   "description": "Distillation mode"
  },
  "query": {
   "type": "string",
   "description": "BM25 focus query when mode=budget"
  },
  "max_tokens": {
   "type": "integer",
   "minimum": 20,
   "description": "Strict token budget ceiling when mode=budget"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "status",
  "roi_proof",
  "data"
 ],
 "properties": {
  "data": {
   "type": "object",
   "description": "Distilled Markdown, structured JSON tables/metadata, skeleton outline, or BM25 budget excerpt."
  },
  "cache": {
   "type": "object",
   "properties": {
    "status": {
     "enum": [
      "HIT",
      "MISS"
     ],
     "type": "string"
    },
    "cache_key": {
     "type": "string"
    },
    "latency_ms": {
     "type": "number"
    }
   }
  },
  "status": {
   "type": "string",
   "description": "Execution status ('ok')"
  },
  "billing": {
   "type": "object",
   "properties": {
    "agent_id": {
     "type": "string"
    },
    "payment_method": {
     "type": "string"
    },
    "fee_charged_usd": {
     "type": "number"
    }
   }
  },
  "roi_proof": {
   "type": "object",
   "properties": {
    "raw_tokens": {
     "type": "integer"
    },
    "tokens_saved": {
     "type": "integer"
    },
    "roi_multiplier": {
     "type": "number"
    },
    "distilled_tokens": {
     "type": "integer"
    },
    "llm_cost_saved_usd": {
     "type": "number"
    },
    "compression_ratio_pct": {
     "type": "number"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/preflight-agentdiet-dev-semantic-html-pruner-web-url-distillation-api-4edb74b7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from preflight.agentdiet.dev](https://www.zero.xyz/host/preflight.agentdiet.dev/llms.txt)