# fetch_response_headers

A read tool on the Allcanuse MCP server.

Agent View of the PolicyLayer registry record for `fetch_response_headers`. HTML page: https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/fetch-response-headers

## Facts

- Tool: `fetch_response_headers`
- Server: Allcanuse (`ra1nyxin/allcanuse-mcp`) — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp.md
- Homepage: https://github.com/ra1nyxin/allcanuse-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": "fetch_response_headers",
    "arguments": {}
  }
}
```

## Why fetch_response_headers is rated Low

Fetching response headers is a read-only network diagnostic operation that queries HTTP metadata without modifying data, executing code, or causing side effects. Consistent with the server's stated purpose of 'network diagnostics.' Low severity due to minimal blast radius—response headers are typically non-sensitive metadata, though confidence is reduced by the absent description.

From the tool's own definition: "Tool name 'fetch_response_headers' indicates retrieval of HTTP response headers from network requests; the prefix 'fetch' denotes a read operation. Description is empty, limiting certainty slightly."

## Use case

AI agents call fetch_response_headers to retrieve information from Allcanuse 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 Allcanuse:

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

## Other tools on Allcanuse (129)

- `cancel_background_task` — Destructive — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/cancel-background-task.md
- `delete_path` — Destructive — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/delete-path.md
- `kill_process` — Destructive — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/kill-process.md
- `capture_camera_photo` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/capture-camera-photo.md
- `capture_screenshot` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/capture-screenshot.md
- `check_c_syntax` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/check-c-syntax.md
- `compile_c_program` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/compile-c-program.md
- `create_background_task` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/create-background-task.md
- `deploy_and_update_service` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/deploy-and-update-service.md
- `evaluate_c_math_expression` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/evaluate-c-math-expression.md
- `extract_archive` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/extract-archive.md
- `format_c_code` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/format-c-code.md
- `generate_c_build_files` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/generate-c-build-files.md
- `generate_c_numeric_test_harness` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/generate-c-numeric-test-harness.md
- `http_request` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/http-request.md
- `optimize_images_for_memory` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/optimize-images-for-memory.md
- `pause_background_task` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/pause-background-task.md
- `ping_host` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/ping-host.md
- `preprocess_c_source` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/preprocess-c-source.md
- `raw_tcp_exchange` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/raw-tcp-exchange.md
- `resume_background_task` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/resume-background-task.md
- `run_cmd` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/run-cmd.md
- `run_powershell` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/run-powershell.md
- `run_shell` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/run-shell.md
- `scan_ports` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/scan-ports.md
- `start_managed_process` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/start-managed-process.md
- `start_process` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/start-process.md
- `stop_managed_process` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/stop-managed-process.md
- `tcp_connect` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/tcp-connect.md
- `trace_route` — Execute — https://policylayer.com/tools/ra1nyxin-allcanuse-mcp/trace-route.md
- …and 99 more: https://policylayer.com/tools/ra1nyxin-allcanuse-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`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=ra1nyxin-allcanuse-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/ra1nyxin-allcanuse-mcp