# check_entity_exists

Check if an entity exists in the knowledge graph

Agent View of the PolicyLayer registry record for `check_entity_exists`. HTML page: https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/check-entity-exists

## Facts

- Tool: `check_entity_exists`
- Server: Daniel LightRAG MCP Server (`desimpkins/daniel-lightrag-mcp`) — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp.md
- Homepage: https://github.com/desimpkins/daniel-lightrag-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": "check_entity_exists",
    "arguments": {}
  }
}
```

## Why check_entity_exists is rated Low

This is a straightforward read operation that queries the knowledge graph to determine entity existence. It has no side effects, does not modify data, and does not execute arbitrary code. The low severity reflects minimal blast radius if misused—an agent could only perform reconnaissance on the knowledge graph structure without causing harm.

From the tool's own definition: "Tool name 'check_entity_exists' and description 'Check if an entity exists in the knowledge graph' indicate a pure query operation that retrieves status information without modifying or deleting data."

## Use case

AI agents call check_entity_exists to retrieve information from Daniel LightRAG MCP Server 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 Daniel LightRAG MCP Server:

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

## Other tools on Daniel LightRAG MCP Server (20)

- `delete_document` — Destructive — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/delete-document.md
- `delete_entity` — Destructive — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/delete-entity.md
- `delete_relation` — Destructive — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/delete-relation.md
- `get_document_status_counts` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-document-status-counts.md
- `get_documents` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-documents.md
- `get_documents_paginated` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-documents-paginated.md
- `get_graph_labels` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-graph-labels.md
- `get_health` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-health.md
- `get_knowledge_graph` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-knowledge-graph.md
- `get_pipeline_status` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-pipeline-status.md
- `get_track_status` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/get-track-status.md
- `hello` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/hello.md
- `query_text` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/query-text.md
- `query_text_stream` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/query-text-stream.md
- `scan_documents` — Read — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/scan-documents.md
- `insert_text` — Write — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/insert-text.md
- `insert_texts` — Write — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/insert-texts.md
- `update_entity` — Write — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/update-entity.md
- `update_relation` — Write — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/update-relation.md
- `upload_document` — Write — https://policylayer.com/tools/desimpkins-daniel-lightrag-mcp/upload-document.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=desimpkins-daniel-lightrag-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/desimpkins-daniel-lightrag-mcp