# Track the current PDF linked from a webpage

**Use case:** 

Give the stable webpage that links to a document and the link text; the Actor resolves the current PDF each run, so a new revision at a new URL is reported as PDF_LINK_CHANGED plus any content changes instead of a lost target. Example: the IRS About Form 1040 page.

## Input

```json
{
  "targets": [
    {
      "targetId": "irs-form-1040",
      "label": "Current IRS Form 1040",
      "pageUrl": "https://www.irs.gov/forms-pubs/about-form-1040",
      "linkText": "Form 1040 PDF"
    }
  ],
  "monitorKey": "linked-pdf",
  "mode": "changesOnly",
  "baselineMode": "emitBaseline",
  "includeTextDiff": true,
  "maxPdfSizeMb": 25,
  "maxPagesPerPdf": 500
}
```

## Output

```json
{
  "targetId": {
    "label": "Target id",
    "format": "string"
  },
  "label": {
    "label": "Label",
    "format": "string"
  },
  "status": {
    "label": "Status",
    "format": "string"
  },
  "changeTypes": {
    "label": "Change types",
    "format": "array"
  },
  "previousPdfUrl": {
    "label": "Previous PDF",
    "format": "string"
  },
  "currentPdfUrl": {
    "label": "Current PDF",
    "format": "string"
  },
  "pageCount": {
    "label": "Page count",
    "format": "integer"
  },
  "previousPageCount": {
    "label": "Previous page count",
    "format": "integer"
  },
  "changedPages": {
    "label": "Changed pages",
    "format": "array"
  },
  "observedAt": {
    "label": "Observed at",
    "format": "string"
  }
}
```

## About this Actor

This example demonstrates how to use [PDF Change Monitor & Linked Document Tracker](https://apify.com/automa-flow/pdf-link-change-monitor.md) with a specific input configuration. Visit the [Actor detail page](https://apify.com/automa-flow/pdf-link-change-monitor.md) to learn more, explore other use cases, and run it yourself.


## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.
This Task's input is already configured above — use it as-is rather than inventing a new one.

- **AI agents and MCP clients** — the [Apify MCP server](https://docs.apify.com/integrations/mcp.md) at `https://mcp.apify.com` (remote, streamable HTTP, OAuth on first use).
- **Agentic workflows and local Actor development** — [Agent Skills](https://apify.com/.well-known/agent-skills/index.json) with the [Apify CLI](https://docs.apify.com/cli/docs.md): `npm install -g apify-cli`, then `apify login`.
- **JavaScript/TypeScript projects** — the official [JS/TS client](https://docs.apify.com/api/client/js/docs.md): `npm install apify-client`.
- **Python projects** — the official [Python client](https://docs.apify.com/api/client/python/docs.md): `pip install apify-client`.
- **Any other language** — the [REST API](https://docs.apify.com/api/v2.md).

For full API examples (JavaScript, Python, CLI, MCP, OpenAPI), see this Task's Actor page: https://apify.com/automa-flow/pdf-link-change-monitor.md

For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt).