# upload_post_cover_from_url

Download an external image URL into R2 and attach it as the post's featuredImage. Replaces the manual flow of pasting external URLs (which break when the source goes down). Validates content-type starts with image/ and rejects payloads larger than 20 MB. No AI credits charged — only standard storage.

Agent View of the PolicyLayer registry record for `upload_post_cover_from_url`. HTML page: https://policylayer.com/tools/io-favcrm-favcrm/upload-post-cover-from-url

## Facts

- Tool: `upload_post_cover_from_url`
- Server: FavCRM (`https://api.favcrm.io/mcp`) — https://policylayer.com/tools/io-favcrm-favcrm.md
- Homepage: https://github.com/favcrm/mcp
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 2 (2 required)
- Recommended policy verdict: Rate-limited

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `postId` | string | yes | The post ID |
| `sourceUrl` | string | yes | Public http(s) URL to fetch the image from. Must respond with an image/* content-type. |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "upload_post_cover_from_url",
    "arguments": {
      "postId": "<postId>",
      "sourceUrl": "<sourceUrl>"
    }
  }
}
```

## Why upload_post_cover_from_url is rated Medium

This tool creates or modifies data (attaches a featured image to a post) without irreversible deletion. While it downloads external content and stores it, the operation is reversible—the image can be replaced or removed. The validation checks (content-type verification, 20 MB limit) provide some guardrails but don't change the fundamental Write category.

From the tool's own definition: "The tool description states it will 'Download an external image URL into R2 and attach it as the post's featuredImage,' which modifies the post by adding/replacing an image attachment. This is a reversible modification operation."

## Use case

AI agents use upload_post_cover_from_url to create or update resources in FavCRM, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your FavCRM environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches FavCRM:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "upload_post_cover_from_url": {
      "limits": [
        {
          "counter": "upload_post_cover_from_url_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on FavCRM (219)

- `cancel_booking` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/cancel-booking.md
- `delete_account` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-account.md
- `delete_campaign` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-campaign.md
- `delete_category` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-category.md
- `delete_contact` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-contact.md
- `delete_custom_field` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-custom-field.md
- `delete_deal` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-deal.md
- `delete_invoice` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-invoice.md
- `delete_knowledge_document` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-knowledge-document.md
- `delete_post` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-post.md
- `delete_post_type` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-post-type.md
- `delete_post_type_field` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-post-type-field.md
- `delete_promotion` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-promotion.md
- `delete_segment` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-segment.md
- `delete_service_package` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-service-package.md
- `delete_tag` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-tag.md
- `delete_task` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/delete-task.md
- `remove_post_block` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/remove-post-block.md
- `void_invoice` — Destructive — https://policylayer.com/tools/io-favcrm-favcrm/void-invoice.md
- `execute_tool` — Execute — https://policylayer.com/tools/io-favcrm-favcrm/execute-tool.md
- `switch_company` — Execute — https://policylayer.com/tools/io-favcrm-favcrm/switch-company.md
- `cancel_subscription` — Financial — https://policylayer.com/tools/io-favcrm-favcrm/cancel-subscription.md
- `create_plan_upgrade_link` — Financial — https://policylayer.com/tools/io-favcrm-favcrm/create-plan-upgrade-link.md
- `create_subscription` — Financial — https://policylayer.com/tools/io-favcrm-favcrm/create-subscription.md
- `enrol_membership` — Financial — https://policylayer.com/tools/io-favcrm-favcrm/enrol-membership.md
- `record_invoice_payment` — Financial — https://policylayer.com/tools/io-favcrm-favcrm/record-invoice-payment.md
- `check_plan_operation` — Read — https://policylayer.com/tools/io-favcrm-favcrm/check-plan-operation.md
- `get_attachment_text` — Read — https://policylayer.com/tools/io-favcrm-favcrm/get-attachment-text.md
- `get_audit_log` — Read — https://policylayer.com/tools/io-favcrm-favcrm/get-audit-log.md
- `get_available_slots` — Read — https://policylayer.com/tools/io-favcrm-favcrm/get-available-slots.md
- …and 189 more: https://policylayer.com/tools/io-favcrm-favcrm.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-favcrm-favcrm · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-favcrm-favcrm