# ncbi-elink

`station__ncbi__ncbi-elink` · external (needs EXECUTION_BACKEND_URL configured) · domain `ncbi` · pv-relevance `pv-adjacent`

Find linked records across NCBI databases.

> **Note:** This tool routes through an external execution backend. If `EXECUTION_BACKEND_URL` is unset on the server, calls return JSON-RPC error `-32603 "Tool execution backend not configured"`. Tools with `backend: native` execute in-process and are always callable.

## Agent metadata

- `idempotent`: unknown
- `read_only`: unknown
- `expected_latency_ms`: unknown (not yet contract-tested)
- `cost_tokens_estimate`: unknown

## Input schema

- `cmd` *string* — Link command (default 'neighbor'). Options: 'neighbor', 'neighbor_score', 'acheck', 'llinks'.
- `db` *string* (required) — Target database (e.g., 'nucleotide', 'pubmed').
- `dbfrom` *string* (required) — Source database (e.g., 'gene').
- `id` *string* (required) — Comma-separated list of source UIDs.

## Example call

```json
POST /api/mcp
Content-Type: application/json

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "station__ncbi__ncbi-elink",
    "arguments": {
      "db": "",
      "dbfrom": "",
      "id": ""
    }
  }
}
```

## Related

- [/tools](/tools) — all 3062 tools
- [/tools/ncbi__ncbi-elink](/tools/ncbi__ncbi-elink) — HTML page
- [/tools/ncbi__ncbi-elink/json](/tools/ncbi__ncbi-elink/json) — JSON form (agent-friendly)
- [/api/mcp](/api/mcp) — endpoint
- [/AGENTS.md](/AGENTS.md) — agent guide