get_performance

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

No annotations were provided, so the description carries the full burden. It states 'Updated daily', which implies timeliness, but does not mention authentication needs, rate limits, or side effects. For a read-only tool, this is adequate but could be more explicit about read-only nature or data coverage limitations.

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 a single sentence followed by a concise list of metrics. Every word contributes value, with no redundancy or fluff. Information is front-loaded with the core purpose.

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 one parameter and no output schema, the description lists all returned metrics, which provides substantial contextual completeness. However, it does not describe the return structure (e.g., JSON format, keys), which would be helpful for agents to parse the 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 input schema has 100% description coverage for the single parameter 'ticker' with examples. The description adds no further semantics beyond affirming that it is for NZX companies. At high schema coverage, a score of 3 is appropriate as the schema does the heavy lifting.

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 explicitly states the tool retrieves stock performance metrics for NZX companies and lists the specific metrics returned. This clearly distinguishes it from sibling tools like 'get_stock_prices' or 'get_market_signals' by focusing on performance ratios and benchmarks.

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 implies usage for NZX stock analysis by listing NZX-specific metrics, but it does not provide explicit guidance on when to use this tool versus alternatives such as 'get_stock_prices' or 'get_technical_signals'. No exclusions or prerequisites are mentioned.

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