alter_schema · Snowflake Developer MCP Server MCP

WHAT IT DOES

What alter_schema does on Snowflake Developer MCP Server

AI agents use alter_schema to create or update resources in Snowflake Developer MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Snowflake Developer MCP Server environment.

WHY IT NEEDS A POLICY

Why alter_schema needs a policy

Altering a schema (rename, move) is a Write operation because it modifies database objects reversibly. However, severity is 'high' rather than 'medium' because schema alterations can have broad downstream impacts on permissions, dependencies, and application functionality across multiple objects that reference the schema.

From the tool's definition Tool name is 'alter_schema' with description 'Alter a schema (rename or move to different database)'. Altering schemas modifies database structure, which is reversible (schemas can be renamed or moved back).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

alter_schema Rate-limited

alter_schema stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "alter_schema": {
      "limits": [
        {
          "counter": "alter_schema_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Snowflake Developer MCP Server, so you can run agents against it safely.

FAQ

Questions about alter_schema

What does the alter_schema tool do? +

Alter a schema (rename or move to different database). It is categorised as a Write tool in the Snowflake Developer MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on alter_schema? +

Register the Snowflake Developer MCP Server MCP server in PolicyLayer and add a rule for alter_schema: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Snowflake Developer MCP Server. Nothing to install.

What risk level is alter_schema? +

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

Can I rate-limit alter_schema? +

Yes. Add a rate_limit block to the alter_schema rule in your PolicyLayer 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 alter_schema completely? +

Set action: deny in the PolicyLayer policy for alter_schema. 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 alter_schema? +

alter_schema is provided by the Snowflake Developer MCP Server MCP server (mcp-tg/snowflake-developer-kit). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.