set_drilldown

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

With no annotations, the description carries the full burden of behavioral disclosure. It discloses that the tool seeds 'the saved drill state (expansionStates)' and explains the effect of each toggle. This goes beyond the input schema. It does not mention whether prior expansion states are overwritten or failure modes, but the disclosed side effect is significant and useful.

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 long and front-loaded with the primary purpose. The first sentence states the action and target. The second explains the toggles. The third discloses the side effect and a usage constraint. No wasted words; every sentence earns its place.

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 moderate-complexity setter tool with no output schema and no annotations, the description covers the essential aspects: what it does, the toggles, the state it modifies, and a requirement. It does not explain return values or error behavior, but given the input schema and the tool's simplicity, it is reasonably complete. Sibling differentiation is implicit but effective.

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 already describes 80% of parameters (page, visual, drillOnClick, expandToNextLevel). The description adds conceptual meaning to the two boolean toggles by explaining their behavioral difference: 'expandToNextLevel (a click expands to the next level rather than drilling)' and 'drillOnClick (single-click drills)'. This clarifies the semantics beyond the terse schema descriptions. reportSessionId is not described in the description, but the schema covers the others adequately.

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's purpose: 'Set DRILL-DOWN behaviour on a visual with a drillable (hierarchy/multi-level) axis'. It specifies the verb (Set), the resource (drill-down behaviour on a visual), and the specific context (drillable axis). It also distinguishes from sibling tools like set_drillthrough by explicitly naming drill-down rather than drillthrough.

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: on visuals with a drillable hierarchy/multi-level axis. It also includes a usage constraint: 'Set at least one toggle'. However, it does not explicitly mention alternatives or exclusions (e.g., when not to use this tool vs. set_drillthrough), which would make guidance more complete.

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