db_schema_save · Schema Engram MCP: Risk & Policy

WHAT IT DOES

What db_schema_save does on Schema Engram

AI agents use db_schema_save to create or update resources in Schema Engram — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Schema Engram environment.

WHY IT NEEDS A POLICY

Why db_schema_save needs a policy

The 'save' operation creates or updates schema entries in the SQLite store. While the description is empty, the context of persistent memory management and the pattern of CRUD operations (create/read/update/delete via sibling tools) clearly positions this as a Write action. It modifies data reversibly and does not delete or execute arbitrary code.

From the tool's definition Tool name 'db_schema_save' combined with server purpose of 'storing table structures and metadata in a local SQLite file' and sibling operations (db_schema_get, db_schema_list, db_schema_update, db_schema_delete) indicate this creates or modifies persistent…

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

db_schema_save Rate-limited

db_schema_save 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": {
    "db_schema_save": {
      "limits": [
        {
          "counter": "db_schema_save_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 Schema Engram, so you can run agents against it safely.

FAQ

Questions about db_schema_save

What does the db_schema_save tool do? +

db_schema_save. It is categorised as a Write tool in the Schema Engram MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on db_schema_save? +

Register the Schema Engram MCP server in PolicyLayer and add a rule for db_schema_save: 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 Schema Engram. Nothing to install.

What risk level is db_schema_save? +

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

Can I rate-limit db_schema_save? +

Yes. Add a rate_limit block to the db_schema_save 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 db_schema_save completely? +

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

db_schema_save is provided by the Schema Engram MCP server (wabox32/schema-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.