set_partition_mode

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

With no annotations, the description carries the full burden. It discloses the default partition behavior and the nuance that the tool 'flips the Mode flag' but may require additional source kind changes. However, it does not mention potential side effects like refresh implications or error conditions if the partition doesn't exist, leaving some behavioral gaps.

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 three sentences with no redundancy. It front-loads the core action and parameters, then adds the default and a caveat in a compact way. Every sentence contributes useful information, and the mention of 'Mode flag' is a nice shorthand.

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 a straightforward setter with 4 parameters and no output schema. The description covers the purpose, default behavior, the hybrid scenario, and a key caveat about source kind. It does not cover possible error conditions or return behavior, but for this simple mutation tool the description is adequately complete for an agent.

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 50% (mode and partition have descriptions; table and sessionId do not). The description adds meaning to the mode values by naming them and clarifies the partition default explicitly ('Defaults to the table's first partition'), reinforcing and extending the schema's description. It also explains the hybrid use case involving set_data_coverage, which helps parameter understanding.

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 uses a specific verb ('Set') with a clear resource ('a partition's storage mode') and enumerates the exact allowed values (Import | DirectQuery | Dual | DirectLake). It also differentiates from related tools by focusing on the Mode flag and explicitly mentioning the complementary tool set_data_coverage for hybrid tables.

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?

Provides explicit usage context: states the default behavior (defaults to the table's first partition) and a specific use case (build a hybrid table using Dual + DirectQuery with set_data_coverage). It also warns about the need to match the partition source kind when switching to DirectLake/DirectQuery, which helps the agent decide when and how to invoke the tool.

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