upsert_lock_rule · Sanka MCP Server MCP: Risk & Policy

WHAT IT DOES

What upsert_lock_rule does on Sanka MCP Server

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

WHY IT NEEDS A POLICY

Why upsert_lock_rule needs a policy

This tool modifies configuration/metadata by creating or updating lock rules that control field-level access constraints. While it doesn't delete data, it reversibly changes system state and authorization rules. The blast radius is medium: misconfiguration could lock critical fields or overly restrict data access, but changes can be reversed.

From the tool's definition Tool name 'upsert_lock_rule' explicitly indicates create or update operation. Description states 'Create or update a record lock rule' and provides specific use cases (locking fields on invoices).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

upsert_lock_rule Rate-limited

upsert_lock_rule 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": {
    "upsert_lock_rule": {
      "limits": [
        {
          "counter": "upsert_lock_rule_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 Sanka MCP Server, so you can run agents against it safely.

FAQ

Questions about upsert_lock_rule

What does the upsert_lock_rule tool do? +

Create or update a record lock rule. For invoices, use lock_scope selected_fields with lock_config.locked_field_keys to lock only chosen fields. It is categorised as a Write tool in the Sanka 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 upsert_lock_rule? +

Register the Sanka MCP Server MCP server in PolicyLayer and add a rule for upsert_lock_rule: 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 Sanka MCP Server. Nothing to install.

What risk level is upsert_lock_rule? +

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

Can I rate-limit upsert_lock_rule? +

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

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

upsert_lock_rule is provided by the Sanka MCP Server MCP server (sankahq/sanka-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.