# decode_protobuf

Decode protobuf binary without a .proto schema. Provide inline data (hex/base64) OR a url to fetch and decode (e.g. gRPC-Connect responses). Analyzes wire format to extract field numbers, types, and values, including nested messages.

Agent View of the PolicyLayer registry record for `decode_protobuf`. HTML page: https://policylayer.com/tools/1600822305-js-reverse-mcp/decode-protobuf

## Facts

- Tool: `decode_protobuf`
- Server: Js Reverse (`1600822305/js-reverse-mcp`) — https://policylayer.com/tools/1600822305-js-reverse-mcp.md
- Homepage: https://github.com/1600822305/js-reverse-mcp
- 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": "decode_protobuf",
    "arguments": {}
  }
}
```

## Why decode_protobuf is rated Low

This tool retrieves and analyzes data (decodes protobuf messages) without modifying, executing, or destroying anything. It is a read-only analysis tool. Low severity because decoding data and reverse-engineering messages poses minimal risk—the output is informational only. Even if misused by an agent, it cannot directly cause damage beyond information disclosure about message structure.

From the tool's own definition: "Tool description states: 'Decode protobuf binary' and 'Analyzes wire format to extract field numbers, types, and values.' These are purely analytical/decoding operations with no modification, deletion, or execution of code."

## Use case

AI agents call decode_protobuf to retrieve information from Js Reverse 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 Js Reverse:

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

## Other tools on Js Reverse (92)

- `clear_browser_cache` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/clear-browser-cache.md
- `clear_cookies` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/clear-cookies.md
- `clear_network_conditions` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/clear-network-conditions.md
- `delete_cookie` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/delete-cookie.md
- `delete_token` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/delete-token.md
- `remove_breakpoint` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-breakpoint.md
- `remove_dom_breakpoint` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-dom-breakpoint.md
- `remove_network_rule` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-network-rule.md
- `remove_xhr_breakpoint` — Destructive — https://policylayer.com/tools/1600822305-js-reverse-mcp/remove-xhr-breakpoint.md
- `add_network_rule` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/add-network-rule.md
- `api_request` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/api-request.md
- `batch_replay` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/batch-replay.md
- `break_on_attribute_modified` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-attribute-modified.md
- `break_on_node_removed` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-node-removed.md
- `break_on_subtree_modified` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-subtree-modified.md
- `break_on_xhr` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/break-on-xhr.md
- `encode_protobuf` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/encode-protobuf.md
- `evaluate_on_callframe` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/evaluate-on-callframe.md
- `evaluate_script` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/evaluate-script.md
- `hook_crypto_functions` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/hook-crypto-functions.md
- `hook_function` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/hook-function.md
- `monitor_events` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-events.md
- `monitor_eventsource` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-eventsource.md
- `monitor_form_submit` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-form-submit.md
- `monitor_input_changes` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/monitor-input-changes.md
- `navigate_page` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/navigate-page.md
- `new_page` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/new-page.md
- `pause` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/pause.md
- `replay_request` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/replay-request.md
- `resume` — Execute — https://policylayer.com/tools/1600822305-js-reverse-mcp/resume.md
- …and 62 more: https://policylayer.com/tools/1600822305-js-reverse-mcp.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=1600822305-js-reverse-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/1600822305-js-reverse-mcp
