# adb_screenshot_diff

Compare the current screen against a saved screenshot baseline. Decodes PNGs and performs pixel-level comparison (RGB channels), reporting exact pixel difference count, percentage, and the bounding box of the changed region. Supports a tolerance threshold for absorbing minor dynamic elements like clocks or notification badges.

Agent View of the PolicyLayer registry record for `adb_screenshot_diff`. HTML page: https://policylayer.com/tools/io-github-fullread-deepadb/adb-screenshot-diff

## Facts

- Tool: `adb_screenshot_diff`
- Server: Deepadb (`deepadb`) — https://policylayer.com/tools/io-github-fullread-deepadb.md
- Install: `npx -y deepadb`
- Homepage: https://github.com/fullread/DeepADB
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

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

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

## Why adb_screenshot_diff is rated Low

This tool retrieves and analyzes visual data from the device screen and compares it against a baseline, but produces only informational output (pixel differences, percentages, bounding boxes). It does not modify device state, execute commands beyond capturing the current visual state, or trigger side effects.

From the tool's own definition: "Tool performs comparison and reporting operations: 'Compare the current screen against a saved screenshot baseline', 'performs pixel-level comparison', 'reporting exact pixel difference count'. No modification, deletion, or execution of arbitrary code."

## Use case

AI agents call adb_screenshot_diff to retrieve information from Deepadb without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "adb_screenshot_diff": {}
  }
}
```

## Other tools on Deepadb (204)

- `adb_clear_data` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-clear-data.md
- `adb_file_move` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-file-move.md
- `adb_forward_remove` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-forward-remove.md
- `adb_logcat_clear` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-logcat-clear.md
- `adb_qemu_images` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-qemu-images.md
- `adb_result_drop` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-result-drop.md
- `adb_reverse_remove` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-reverse-remove.md
- `adb_rm` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-rm.md
- `adb_tunnel_close` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-tunnel-close.md
- `adb_uninstall` — Destructive — https://policylayer.com/tools/io-github-fullread-deepadb/adb-uninstall.md
- `adb_a11y_audit` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-a11y-audit.md
- `adb_airplane_cycle` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-airplane-cycle.md
- `adb_airplane_mode` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-airplane-mode.md
- `adb_at_batch` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-at-batch.md
- `adb_at_probe` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-at-probe.md
- `adb_at_send` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-at-send.md
- `adb_batch_actions` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-batch-actions.md
- `adb_build_and_install` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-build-and-install.md
- `adb_ci_run_tests` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-ci-run-tests.md
- `adb_ci_wait_boot` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-ci-wait-boot.md
- `adb_connect` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-connect.md
- `adb_disconnect` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-disconnect.md
- `adb_dumpsys` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-dumpsys.md
- `adb_emulator_start` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-emulator-start.md
- `adb_emulator_stop` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-emulator-stop.md
- `adb_farm_run` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-farm-run.md
- `adb_file_chmod` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-file-chmod.md
- `adb_file_chown` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-file-chown.md
- `adb_force_stop` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-force-stop.md
- `adb_forward` — Execute — https://policylayer.com/tools/io-github-fullread-deepadb/adb-forward.md
- …and 174 more: https://policylayer.com/tools/io-github-fullread-deepadb.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-github-fullread-deepadb · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-fullread-deepadb