# http_check

Resolves a URL and reports what actually happens to it — final status, the full redirect chain, content type and page title. Link rot is faster than it feels: one agent measured seven dead URLs out of 286 across fourteen days. This handles the three cases a naive checker gets wrong: an arXiv v1 to v2 redirect is a version change, not a break; a 403 is a blocked crawler, not a dead page; and a DOI can return 200 while the page behind it is now a retraction notice, which is the worst case because a simple status check passes and the reader gets something else. Response bodies are never returned — only status, headers, title and flags.

Agent View of the PolicyLayer registry record for `http_check`. HTML page: https://policylayer.com/tools/com-fluentedi-tools/http-check

## Facts

- Tool: `http_check`
- Server: Tools (`https://fluentedi.com/mcp`) — https://policylayer.com/tools/com-fluentedi-tools.md
- Homepage: https://github.com/https://fluentedi.com/mcp
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 3 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `url` | string | yes | URL to check. |
| `timeout_ms` | integer | no | Per-request timeout in milliseconds. |
| `max_redirects` | integer | no | How many redirects to follow. |

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": "http_check",
    "arguments": {
      "url": "<url>"
    }
  }
}
```

## Why http_check is rated Low

Even though http_check only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

Risk signals: Accepts URL/endpoint input (url)

## Use case

AI agents call http_check to retrieve information from Tools 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 Tools:

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

## Other tools on Tools (16)

- `cron_next` — Execute — https://policylayer.com/tools/com-fluentedi-tools/cron-next.md
- `edi_build` — Execute — https://policylayer.com/tools/com-fluentedi-tools/edi-build.md
- `edi_parse` — Execute — https://policylayer.com/tools/com-fluentedi-tools/edi-parse.md
- `edi_validate` — Read — https://policylayer.com/tools/com-fluentedi-tools/edi-validate.md
- `hash` — Read — https://policylayer.com/tools/com-fluentedi-tools/hash.md
- `http_assert` — Read — https://policylayer.com/tools/com-fluentedi-tools/http-assert.md
- `json_query` — Read — https://policylayer.com/tools/com-fluentedi-tools/json-query.md
- `json_repair` — Read — https://policylayer.com/tools/com-fluentedi-tools/json-repair.md
- `math_eval` — Read — https://policylayer.com/tools/com-fluentedi-tools/math-eval.md
- `time_diff` — Read — https://policylayer.com/tools/com-fluentedi-tools/time-diff.md
- `time_now` — Read — https://policylayer.com/tools/com-fluentedi-tools/time-now.md
- `time_window` — Read — https://policylayer.com/tools/com-fluentedi-tools/time-window.md
- `tool_describe` — Read — https://policylayer.com/tools/com-fluentedi-tools/tool-describe.md
- `tool_search` — Read — https://policylayer.com/tools/com-fluentedi-tools/tool-search.md
- `time_convert` — Write — https://policylayer.com/tools/com-fluentedi-tools/time-convert.md
- `tool_call` — Write — https://policylayer.com/tools/com-fluentedi-tools/tool-call.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=com-fluentedi-tools · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-fluentedi-tools
