sector_rotation

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

Annotations declare readOnlyHint=true, confirming a safe read operation. Description adds behavioral context by specifying that the tool returns ranked performance, which goes beyond the annotation. No contradictions. Could mention data freshness or update frequency, but not required.

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?

Two sentences with zero wasted words. Front-loaded with clear purpose, then usage hint. Perfectly concise.

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 only one parameter, no nested objects, and an output schema exists, the description adequately covers purpose and usage. It could mention that it is based on SPDR ETFs, which it does. Complete for a simple 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?

Only one parameter 'period' with 100% schema description coverage. The schema already explains the possible values and default. The description does not add additional meaning beyond what the schema provides, so baseline 3 is appropriate.

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?

Description clearly states 'Sector performance ranking via SPDR sector ETFs' and 'Returns performance of all 11 GICS sectors ranked by return.' This specifies the verb (returns), resource (sector performance), and scope (all 11 sectors ranked). It distinguishes from sibling tools like market_overview or technical_analysis by focusing specifically on sector rotation.

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?

States 'Useful for identifying market leadership and rotation trends,' providing clear usage context. However, it does not explicitly mention when not to use or name alternative tools for different scenarios.

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