change_column_type

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

With no annotations, the description tells the agent that the tool appends Table.TransformColumnTypes to the M query, disclosing the side effect on the query. It also warns about silent type-conversion corruption on mixed-locale sources and recommends culture as a fix, going beyond simple schema info.

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 succinct and well-structured: it gives the purpose first, then the syntax, then the culture caveat. Every sentence adds value—there is no filler or redundant information.

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?

The tool is moderately complex due to the culture handling, and the description covers the core operation, the M query side effect, syntax, and valid types. It doesn't detail return values, but with no output schema, that's acceptable. A mention of handling multiple columns via comma-separation is included, making it largely complete.

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 60%, and the description adds meaningful semantics for the key parameters: it defines the exact 'column:type' syntax, lists valid type values, and explains the purpose of culture. It does not add descriptions for sessionId, table, or partitionName, but those are likely standard across tools.

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 'Power Query Change Type: set the data type of one or more columns', using a specific verb and resource. It further clarifies the exact M function (Table.TransformColumnTypes) and gives concrete examples, clearly distinguishing it from similar siblings like 'set_column_data_type'.

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 provides clear context for when to use the tool (changing column types in Power Query) and even explains when the culture parameter is needed (mixed-locale sources). However, it does not explicitly state when not to use it or name alternatives, so it falls short of a 5.

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