@neitherai/mcp-server

Get your key: https://www.neither.online/start/?product=dev&utm_source=npm

Stdio MCP server for Cursor and Claude Desktop. Connects to Neither decision memory with cited provenance — not anonymous text chunks.

Free beta — no waitlist required. Paste the workspace API key using one of the two setup paths below.

Claude Code (claude mcp add)

claude mcp add neither -s user -e NEITHER_API_KEY=sk_ctx_… -e NEITHER_API_BASE=https://api.neither.online -- npx -y @neitherai/mcp-server@latest

stdio / mcp.json (Cursor, Claude Desktop)

Add this to Cursor MCP settings (mcp.json) or Claude Desktop config:

{
  "mcpServers": {
    "neither": {
      "command": "npx",
      "args": ["-y", "@neitherai/mcp-server@latest"],
      "env": {
        "NEITHER_API_KEY": "sk_ctx_…",
        "NEITHER_API_BASE": "https://api.neither.online"
      }
    }
  }
}

NEITHER_API_KEY is required. NEITHER_API_BASE defaults to https://api.neither.online when omitted.

Environment variables

| Variable | Required | Description | | ------------------ | -------- | ------------------------------------------------------------ | | NEITHER_API_KEY | Yes | Workspace key with memory_read (and can_ingest for push) | | NEITHER_API_BASE | No | API host (default: https://api.neither.online) |

Tools

tools/list includes a human-readable title plus readOnlyHint / destructiveHint on every tool (Anthropic desktop-extension review).

• memory_search — natural-language search over workspace decision memory (read-only)
• memory_for_file — cited Decision/Rejected/Constraint prose for a repo file path (read-only)
• memory_snippet_fetch — fetch verbatim snippet by source_id (read-only)
• memory_timeline — time-ordered memory view for a topic or anchor (read-only)
• memory_push — close a decision or seed an ADR snippet with provenance (additive write)

When to call Neither

Call Neither at delivery forks and planning writes — when choosing between approaches or aligning strategy — not on every file open or for passive archaeology.

Documentation

Full tool reference and provenance fields: https://www.neither.online/docs/mcp