get_sector_performance

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

No annotations are provided, so the description carries the full behavioral burden. It transparently discloses the return contents (latest price, 1d/5d/20d returns), the universe (all GICS sector ETFs), the ordering (ranked by 1-day change), and the inclusion of the SPY benchmark. It does not mention data freshness or error conditions, but the core behavior is well disclosed.

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?

A single sentence efficiently front-loads the purpose and packs in the scope, metrics, sort order, and benchmark without any wasted words. Every element adds value.

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 no-parameter, no-output-schema tool, the description is highly complete: it tells the agent what data is included, how it is sorted, and that a benchmark is present. It does not enumerate exact field names, but that is not essential given the simple and well-described output.

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 tool has zero parameters, so no parameter documentation is needed; the baseline is 4. The description adds context about the output universe and benchmark, which is helpful but not parameter-related.

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 a specific verb and resource: it provides a sector rotation view with latest price and 1d/5d/20d returns for every GICS sector ETF, ranked by 1-day change, plus the SPY benchmark. This distinguishes it from siblings like list_sectors, get_sector_members, and get_quote by specifying the exact output and scope.

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 phrase 'Sector rotation view' implies a use case, but the description does not explicitly state when to use this tool versus alternatives such as get_sector_members or list_sectors. There is no clear when-to-use or when-not-to-use guidance, leaving the selection largely to inference.

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