powerbi-desktop-mcp

find_query_diagnostics

Locate and read recorded Power Query diagnostics from Power BI Desktop to inspect step timings, data source queries, row counts, and query folding details after a manual diagnostics session.

Instructions

Find and read output from Power BI Desktop's built-in Query Diagnostics feature, if you've recorded a session. This plugin can't start/stop Query Diagnostics itself -- it's a manual step in the Power Query Editor's Tools tab (Start Diagnostics -> do the refresh you want traced -> Stop Diagnostics) with no local API to trigger it -- but once you've recorded one, this finds the resulting "Diagnostics" queries by name and, for any that were loaded into the model, returns the actual traced rows (step-by-step timing, data source queries, row counts, whether query folding happened, and so on -- the real intermediate evaluation data list_power_query's step breakdown can't provide). If the diagnostics queries exist but weren't loaded into the model, this tells you that and how to fix it rather than returning nothing.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`instance`	Yes
`max_rows`	No

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 23, 2026

TDQS

A3.9/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden, and it does well: it explains the manual recording prerequisite, the inability to trigger diagnostics, the fallback behavior when diagnostics queries exist but were not loaded, and what kind of traced rows are returned. It stops short of covering row-limit behavior or instance-scoping details.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The purpose and prerequisite are front-loaded, and most sentences add useful context. The paragraph is dense and somewhat run-on, with minor redundancy, but it does not waste much space.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description is strong on workflow, return content, and failure cases, and an output schema exists for return shape. However, for a tool with no annotations and 0% schema description coverage, the missing explanation of the required `instance` parameter and `max_rows` limit leaves a meaningful completeness gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters1/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% and the description never mentions either parameter. It does not explain what the required `instance` value should be or what `max_rows` controls, leaving both parameters undocumented.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb and resource: finding and reading Power BI Desktop Query Diagnostics output. It clearly distinguishes this from sibling capabilities by contrasting the traced intermediate evaluation data with list_power_query's step breakdown.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives an explicit prerequisite: a diagnostics session must already have been manually recorded via the Power Query Editor. It also states what the tool cannot do (start/stop diagnostics) and names an alternative sibling limitation, so the agent can choose correctly.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.