# perception_fetch_tile

Fetch the least-cloudy Sentinel-2 L2A tile covering a given H3 cell from Microsoft Planetary Computer. Returns signed COG band URLs for all 6 Prithvi/Clay spectral bands (B02 Blue, B03 Green, B04 Red, B8A NIR, B11 SWIR1, B12 SWIR2), plus tile metadata. The tile is cached in memory for subsequent perception_classify or perception_embed calls.

Agent View of the PolicyLayer registry record for `perception_fetch_tile`. HTML page: https://policylayer.com/tools/com-geiant-mcp-agentcore/perception-fetch-tile

## Facts

- Tool: `perception_fetch_tile`
- Server: Mcp Agentcore (`https://packagesmcp-perception-production.up.railway.app/mcp`) — https://policylayer.com/tools/com-geiant-mcp-agentcore.md
- Homepage: https://github.com/GNS-Foundation/geiant
- Risk category: Read (Low risk)
- Registry record: grade D, identity unverified
- Server auth posture: open
- Server rate-limited: no
- Parameters: 4 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `h3_cell` | string | yes | H3 cell ID at any resolution. |
| `days_back` | number | no | Days to search back. Default: 30. |
| `timestamp` | string | no | ISO 8601 datetime. Search back from this point. Defaults to now. |
| `max_cloud_cover` | number | no | Max cloud cover %. Default: 20. |

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": "perception_fetch_tile",
    "arguments": {
      "h3_cell": "<h3_cell>"
    }
  }
}
```

## Why perception_fetch_tile is rated Low

This tool retrieves satellite imagery data and metadata without side effects. It fetches pre-existing Sentinel-2 tiles and returns URLs and metadata for subsequent processing by other tools (perception_classify, perception_embed). There is no creation, modification, deletion, code execution, or financial transaction involved. The action is purely a data retrieval operation with no capacity to modify or destroy data.

From the tool's own definition: "Tool description uses retrieval language: 'Fetch', 'Returns signed COG band URLs', 'cached in memory'. No modification, deletion, or execution of external operations mentioned."

## Use case

AI agents call perception_fetch_tile to retrieve information from Mcp Agentcore 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 Mcp Agentcore:

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

## Other tools on Mcp Agentcore (7)

- `perception_classify` — Execute — https://policylayer.com/tools/com-geiant-mcp-agentcore/perception-classify.md
- `perception_embed` — Other — https://policylayer.com/tools/com-geiant-mcp-agentcore/perception-embed.md
- `gns_get_compliance_report` — Read — https://policylayer.com/tools/com-geiant-mcp-agentcore/gns-get-compliance-report.md
- `gns_get_trust_score` — Read — https://policylayer.com/tools/com-geiant-mcp-agentcore/gns-get-trust-score.md
- `gns_verify_chain` — Read — https://policylayer.com/tools/com-geiant-mcp-agentcore/gns-verify-chain.md
- `gns_roll_epoch` — Write — https://policylayer.com/tools/com-geiant-mcp-agentcore/gns-roll-epoch.md
- `perception_weather` — Write — https://policylayer.com/tools/com-geiant-mcp-agentcore/perception-weather.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-geiant-mcp-agentcore · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-geiant-mcp-agentcore