# get_diffbeam_state

Check whether DiffBeam protocol, tools, or catalog data changed. If changed is true, refresh tool schemas and repeat any catalog searches before citing part numbers. This tool is read-only, fast, and stateless.

Agent View of the PolicyLayer registry record for `get_diffbeam_state`. HTML page: https://policylayer.com/tools/com-gaussian-beam-diffbeam/get-diffbeam-state

## Facts

- Tool: `get_diffbeam_state`
- Server: DiffBeam Gaussian Beam Optics (`https://catalog-api.gaussian-beam.com/mcp/`) — https://policylayer.com/tools/com-gaussian-beam-diffbeam.md
- Homepage: https://github.com/RiaRosenauer/diffbeam-mcp
- Risk category: Read (Low risk)
- Registry record: grade C, identity unverified
- Server auth posture: open
- Server rate-limited: no
- Parameters: 3
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `known_server_revision` | object | no | Previously observed server revision, if any. |
| `known_catalog_revision` | object | no | Previously observed catalog revision, if any. |
| `known_tool_schema_revision` | object | no | Previously observed tool schema revision, if any. |

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": "get_diffbeam_state",
    "arguments": {}
  }
}
```

## Why get_diffbeam_state is rated Low

Even though get_diffbeam_state 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.

## Use case

AI agents call get_diffbeam_state to retrieve information from DiffBeam Gaussian Beam Optics 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 DiffBeam Gaussian Beam Optics:

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

## Other tools on DiffBeam Gaussian Beam Optics (3)

- `search_fiber_collimators` — Read — https://policylayer.com/tools/com-gaussian-beam-diffbeam/search-fiber-collimators.md
- `search_fibers` — Read — https://policylayer.com/tools/com-gaussian-beam-diffbeam/search-fibers.md
- `search_lenses` — Read — https://policylayer.com/tools/com-gaussian-beam-diffbeam/search-lenses.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-gaussian-beam-diffbeam · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-gaussian-beam-diffbeam