# gribstream_validate_request

NO AUTH / PUBLIC / READ-ONLY. Validates the basic shape, exact selector tuples, and expression syntax of a proposed GribStream /timeseries or /runs request without sending it. This tool does not execute the request, query weather values, or return forecast data. Use this before returning any hand-edited curl or when changing a request from one dataset to another.

Agent View of the PolicyLayer registry record for `gribstream_validate_request`. HTML page: https://policylayer.com/tools/com-gribstream-mcp/gribstream-validate-request

## Facts

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

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `dataset` | string | yes | Dataset code, for example gfs, ifsoper, nbm, hrrr, or urma. |
| `request` | object | yes | Request body to validate. Omit asOf unless the user explicitly asks for backtesting, time travel, what was known then, or a historical model-run cutoff for /tim |
| `endpoint` | string | yes | Endpoint to validate. |

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": "gribstream_validate_request",
    "arguments": {
      "dataset": "<dataset>",
      "request": {},
      "endpoint": "<endpoint>"
    }
  }
}
```

## Why gribstream_validate_request is rated Low

Even though gribstream_validate_request 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 freeform code/query input (request.expressions[].expression) · Accepts URL/endpoint input (endpoint) · High parameter count (37 properties)

## Use case

AI agents call gribstream_validate_request to retrieve information from GribStream MCP 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 GribStream MCP:

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

## Other tools on GribStream MCP (11)

- `gribstream_build_runs_request` — Execute — https://policylayer.com/tools/com-gribstream-mcp/gribstream-build-runs-request.md
- `gribstream_build_timeseries_request` — Execute — https://policylayer.com/tools/com-gribstream-mcp/gribstream-build-timeseries-request.md
- `gribstream_get_dataset` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-get-dataset.md
- `gribstream_get_expression_reference` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-get-expression-reference.md
- `gribstream_get_parameter` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-get-parameter.md
- `gribstream_list_datasets` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-list-datasets.md
- `gribstream_list_parameters` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-list-parameters.md
- `gribstream_list_shared_parameters` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-list-shared-parameters.md
- `gribstream_query_runs` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-query-runs.md
- `gribstream_query_timeseries` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-query-timeseries.md
- `gribstream_resolve_shared_parameter` — Read — https://policylayer.com/tools/com-gribstream-mcp/gribstream-resolve-shared-parameter.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-gribstream-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-gribstream-mcp