add_mcp_server

Add a new MCP server to the configuration

Accepts freeform code/query input (mcpServer.command); Accepts URL/endpoint input (mcpServer.url); High parameter count (11 properties)

Part of the Mcp All MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.

@antonytm/mcp-all Write Risk 3/5

// WHEN AI AGENTS USE THIS TOOL

AI agents use add_mcp_server to create or modify resources in Mcp All. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.

// WHY ENFORCE A POLICY ON ADD_MCP_SERVER

Without a policy, an AI agent could call add_mcp_server repeatedly, creating or modifying resources faster than any human could review. Intercept's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Mcp All.

// RECOMMENDED POLICY

Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.

io-github-antonytm-mcp-all.yaml

tools:
  add_mcp_server:
    rules:
      - action: allow
        rate_limit:
          max: 30
          window: 60

See the full Mcp All policy for all 5 tools.

// DETAILS

Tool Name add_mcp_server

Category Write

MCP Server Mcp All MCP Server

Risk Level Medium

// MORE MCP ALL TOOLS

Destructive remove_mcp_server Read mcp configuration Read refresh_mcp_index Read search

// WHAT CAN GO WRONG

Agents calling write-class tools like add_mcp_server have been implicated in these attack patterns. Read the full case and prevention policy for each:

Browse the full MCP Attack Database →

// OTHER WRITE TOOLS ACROSS MCP SERVERS

Other tools in the Write risk category across the catalogue. The same policy patterns (rate-limit, validate) apply to each.

AbraFlexi contact_create AbraFlexi contact_update AbraFlexi evidence_create AbraFlexi evidence_update AbraFlexi invoice_issued_update AbraFlexi invoice_received_create

// RELATED READING

// FAQ

What does the add_mcp_server tool do? +

Add a new MCP server to the configuration. It is categorised as a Write tool in the Mcp All MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_mcp_server? +

Add a rule in your Intercept YAML policy under the tools section for add_mcp_server. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Mcp All MCP server.

What risk level is add_mcp_server? +

add_mcp_server is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit add_mcp_server? +

Yes. Add a rate_limit block to the add_mcp_server rule in your Intercept policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block add_mcp_server completely? +

Set action: deny in the Intercept policy for add_mcp_server. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides add_mcp_server? +

add_mcp_server is provided by the Mcp All MCP server (@antonytm/mcp-all). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.

add_mcp_server

Enforce policies on Mcp All