MCP 服务器

ServiceNow MCP Server

Connects Claude Desktop to a ServiceNow instance, enabling natural-language interactions to read incidents, inspect CMDB and table schemas, and create records with guardrails like update set scoping and dry-run preview.

README

ServiceNow Developer Actions — MCP Server

An MCP server that connects Claude Desktop (or any MCP client) to a ServiceNow instance, exposing guarded developer actions as natural-language tools. Claude can read incidents, inspect CMDB and table schemas, and create records — with every write isolated to a scoped Update Set, restricted to an allowlist of tables, and protected by a dry-run preview.

Built with FastMCP, a typed REST client, and an explicit guardrail layer — the difference between an LLM API wrapper and an agent tool you'd let near a production instance.

Why this project

This demonstrates two skill sets at once:

AI engineering / agent architecture — agentic tool design with safety rails: input schemas (Pydantic), an allowlist + blocklist for writable tables, automatic Update Set scoping, and a dry_run mode on risky tools so the model previews intent before mutating anything.
ServiceNow integration architecture — a resilient Table API client with OAuth2 (with Basic-auth fallback), token refresh on 401, and exponential backoff on 429/5xx, plus CMDB and sys_dictionary introspection tools.

Architecture

Claude Desktop
   │  (MCP protocol over stdio)
   ▼
FastMCP Server  ── server.py
   │
   ├── tools (read)   get_incidents · query_table · describe_table · get_cmdb_cis
   ├── tools (write)  create_incident · create_script_include   ← guarded
   │
   ├── guardrails.py  allowlist · blocklist · update-set scoping · dry-run
   ▼
ServiceNowClient  ── client.py   (OAuth2 / Basic · retry · backoff · typed errors)
   │  REST (Table API)
   ▼
ServiceNow instance (PDI)

Tools

Tool	Type	Notes
`get_incidents`	read	Newest-first, active filter
`query_table`	read	GlideRecord-style query on any table
`describe_table`	read	Field inspection via `sys_dictionary`
`get_cmdb_cis`	read	List CIs from a CMDB class
`create_incident`	write	Allowlisted, Update-Set scoped, `dry_run`
`create_script_include`	write	`dry_run=True` by default

Guardrails

Writable allowlist — only dev-artifact tables (incident, sys_script_include, sys_script, …). Security/identity tables (sys_user, sys_security_acl, …) are explicitly blocked.
Update Set scoping — every write lands in a named, reviewable Update Set, never in Default.
Dry-run — risky tools echo what would happen instead of executing.

Setup

git clone <your-repo-url> && cd servicenow-mcp
python -m venv .venv && source .venv/bin/activate   # Windows: .venv\Scripts\activate
pip install -e ".[dev]"
cp .env.example .env        # fill in your PDI URL + credentials
pytest                      # 6 tests, all green

Connect to Claude Desktop

Add to claude_desktop_config.json (Developer → Open App Configuration File), then restart:

{
  "mcpServers": {
    "servicenow": {
      "command": "python",
      "args": ["-m", "servicenow_mcp.server"],
      "cwd": "/absolute/path/to/servicenow-mcp/src",
      "env": {
        "SN_URL": "https://dev.service-now.com/",
        "SN_USER": "user",
        "SN_PASS": "pass",
        "SN_UPDATE_SET": "MCP Automated Changes"
      }
    }
  }
}