# canvas_open_url

Open a remote web page inside the canvas window for full in-app browsing.

Agent View of the PolicyLayer registry record for `canvas_open_url`. HTML page: https://policylayer.com/tools/cowork-os/canvas-open-url

## Facts

- Tool: `canvas_open_url`
- Server: CoWork OS (`CoWork-OS/CoWork-OS`) — https://policylayer.com/tools/cowork-os.md
- Homepage: https://github.com/CoWork-OS/CoWork-OS
- Risk category: Execute (High risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

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

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "canvas_open_url",
    "arguments": {}
  }
}
```

## Why canvas_open_url is rated High

This tool fetches and renders an arbitrary remote URL inside the application, constituting an external operation with side effects. It can trigger network requests to arbitrary destinations, potentially load malicious content, execute in-page scripts, or be used for SSRF-like attacks against internal resources. The action depends heavily on the URL argument provided, classifying it as Execute rather than a pure Read.

From the tool's own definition: "Open a remote web page inside the canvas window for full in-app browsing"

## Use case

AI agents invoke canvas_open_url to trigger actions in CoWork OS. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call: builds kicked off, notifications sent, workflows started.

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "canvas_open_url": {
      "limits": [
        {
          "counter": "canvas_open_url_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on CoWork OS (341)

- `cancel_agent` — Destructive — https://policylayer.com/tools/cowork-os/cancel-agent.md
- `cancel_video_generation_job` — Destructive — https://policylayer.com/tools/cowork-os/cancel-video-generation-job.md
- `cloud_sandbox_delete` — Destructive — https://policylayer.com/tools/cowork-os/cloud-sandbox-delete.md
- `delete_file` — Destructive — https://policylayer.com/tools/cowork-os/delete-file.md
- `disable_macos_launch_agents` — Destructive — https://policylayer.com/tools/cowork-os/disable-macos-launch-agents.md
- `domain_dns_delete` — Destructive — https://policylayer.com/tools/cowork-os/domain-dns-delete.md
- `google-workspace.calendar_event_delete` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.calendar-event-delete.md
- `google-workspace.slides_delete_slide` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.slides-delete-slide.md
- `google-workspace.tasks_clear_completed` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.tasks-clear-completed.md
- `google-workspace.tasks_delete` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.tasks-delete.md
- `google-workspace.tasks_lists_delete` — Destructive — https://policylayer.com/tools/cowork-os/google-workspace.tasks-lists-delete.md
- `kg_delete_edge` — Destructive — https://policylayer.com/tools/cowork-os/kg-delete-edge.md
- `kg_delete_entity` — Destructive — https://policylayer.com/tools/cowork-os/kg-delete-entity.md
- `skill_delete` — Destructive — https://policylayer.com/tools/cowork-os/skill-delete.md
- `supermemory_forget` — Destructive — https://policylayer.com/tools/cowork-os/supermemory-forget.md
- `blender.render_view` — Execute — https://policylayer.com/tools/cowork-os/blender.render-view.md
- `browser_act_batch` — Execute — https://policylayer.com/tools/cowork-os/browser-act-batch.md
- `browser_attach` — Execute — https://policylayer.com/tools/cowork-os/browser-attach.md
- `browser_back` — Execute — https://policylayer.com/tools/cowork-os/browser-back.md
- `browser_click` — Execute — https://policylayer.com/tools/cowork-os/browser-click.md
- `browser_close` — Execute — https://policylayer.com/tools/cowork-os/browser-close.md
- `browser_close_tab` — Execute — https://policylayer.com/tools/cowork-os/browser-close-tab.md
- `browser_drag` — Execute — https://policylayer.com/tools/cowork-os/browser-drag.md
- `browser_emulate` — Execute — https://policylayer.com/tools/cowork-os/browser-emulate.md
- `browser_evaluate` — Execute — https://policylayer.com/tools/cowork-os/browser-evaluate.md
- `browser_fill` — Execute — https://policylayer.com/tools/cowork-os/browser-fill.md
- `browser_forward` — Execute — https://policylayer.com/tools/cowork-os/browser-forward.md
- `browser_handle_dialog` — Execute — https://policylayer.com/tools/cowork-os/browser-handle-dialog.md
- `browser_hover` — Execute — https://policylayer.com/tools/cowork-os/browser-hover.md
- `browser_navigate` — Execute — https://policylayer.com/tools/cowork-os/browser-navigate.md
- …and 311 more: https://policylayer.com/tools/cowork-os.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`

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