warm_directlake_cache

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

No annotations are provided, so the description carries the full burden. It discloses that it runs a specific DAX query (TOPN(1, SELECTCOLUMNS(...))) over listed columns or the entire table, and that it returns the query and result. This is transparent about the operation, though it does not mention potential side effects like memory pressure or permission requirements.

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?

The description is concise and front-loaded: it states the purpose, mechanism, parameter format, and return value in three tight sentences. No filler or redundancy.

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?

For a tool with no output schema and three parameters, the description covers the core purpose, mechanism, column parameter usage, and return value. It is missing explanation of sessionId and prerequisites (e.g., Direct Lake mode), but overall it provides enough context for a capable agent to select and invoke the 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?

Schema coverage is only 33% (only columns has a description). The description adds clarifying meaning for the table parameter (the table being warmed) and columns (comma-separated, omit for all), but it does not explain the required sessionId parameter at all. It partially compensates for the coverage gap but leaves a key parameter undocumented.

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 opens with a specific verb and resource ('Warm the Direct Lake cache') and explains the exact mechanism (run EVALUATE TOPN(1, SELECTCOLUMNS(...))). It clearly distinguishes this from sibling tools like refresh_dataset or check_directlake_fallback by focusing on cache warming to eliminate first-query latency.

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 states when to use the tool: to force columns resident and remove first-query latency. It also clarifies the columns parameter ('omit for all'), implying the scope. It does not explicitly name alternatives or exclusions, but the context is clear enough.

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