run_dax

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

With no annotations, the description carries the behavioral transparency burden. It discloses the return format (columns + rows) and the behavior of accepting bare table expressions with EVALUATE prepended. It does not mention side effects or permissions, but as a query tool, the described behavior is reasonably transparent.

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

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

Two sentences that front-load the purpose, then add syntax details, then use cases. Every sentence earns its place, with no unnecessary words.

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

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

Although there is no output schema, the description explicitly explains the return values ('columns + rows'). It includes use cases and syntax variations. It omits sessionId explanation and error behavior, but overall it is adequate for a query execution tool.

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

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

The schema covers dax and maxRows with descriptions; sessionId is undocumented. The description adds nuance to dax (prepending EVALUATE) but not to sessionId. With 67% parameter coverage, the description partially compensates but does not fully address the missing parameter.

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

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

The description clearly states 'Run a DAX query against the live model and RETURN the result rows', providing a specific verb, resource, and output. It also explains accepted query forms and distinguishes from siblings like run_dax_as_role and validate_dax by focusing on general execution and result retrieval.

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

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

The description gives explicit use cases: 'use to verify a refresh, get row counts, check date ranges, or preview data.' While it does not name alternatives or exclusions, it provides clear context for when the tool is appropriate, which is sufficient.

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