set_tablix_corner

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

With no annotations, the description carries full burden. It discloses replacement of existing TablixCorner, the return including changed status, and the refusal condition. However, it does not discuss permissions, side effects beyond replacement, or error handling for simultaneous text/expression.

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 at three sentences, front-loaded with purpose, and every sentence provides necessary detail without 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?

Given the tool has 4 parameters, no output schema, and no annotations, the description partially explains parameters and behavior but omits explanations for 'path' and 'tablix_name'. Return value is mentioned, but error handling for mutually exclusive parameters is absent.

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 0%, so description must compensate. It adds meaning for 'text' (literal value) and 'expression' (VB.NET formula), but does not explain 'path' or 'tablix_name', both required. The description fails to describe two of four parameters, leaving significant gaps.

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 the tool writes a TablixCorner block, specifying it's the top-left cell of a matrix tablix holding a row-axis caption. The verb 'Write' and resource 'TablixCorner' are precise, distinguishing it from sibling tools like set_tablix_size or add_tablix_column.

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 explains to pass text or expression (mutually exclusive), and notes that it refuses if the tablix has no named column group. This provides context on when the tool is applicable, but does not explicitly compare to alternative tools for setting the corner.

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