Evaluate a measure or table row count under EVERY RLS role and return a pass/fail matrix vs the unrestricted baseline, flagging roles that see everything (no filtering) or nothing. Tests row-level security systematically on the connected Desktop model. Always restores the cleared role afterward.
AI agents call rls_test_harness to retrieve information from Power BI MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries Power BI model state (measure values, row counts) under different RLS contexts to audit security configuration. While it temporarily clears roles during testing, the description states it 'always restores' afterward, making the operation reversible. The core function is inspection/testing (Read) rather than modification.
From the tool's definition Tool 'rls_test_harness' evaluates and returns a 'pass/fail matrix' comparing measure/row counts across RLS roles vs baseline.
Risk signalsBulk/mass operation — affects multiple targets
Attacks that exploit this kind of access
Evaluate a measure or table row count under EVERY RLS role and return a pass/fail matrix vs the unrestricted baseline, flagging roles that see everything (no filtering) or nothing. Tests row-level security systematically on the connected Desktop model. Always restores the cleared role afterward. It is categorised as a Read tool in the Power BI MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Power BI MCP Server MCP server in PolicyLayer and add a rule for rls_test_harness: 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 Power BI MCP Server. Nothing to install.
rls_test_harness is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the rls_test_harness 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.
Set action: deny in the PolicyLayer policy for rls_test_harness. 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.
rls_test_harness is provided by the Power BI MCP Server MCP server (sulaiman013/powerbi-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.