show_benchmark

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

Given no annotations, the description discloses two distinct behaviors: using daily snapshot history when available, otherwise falling back to cost-basis vs current value. This provides useful transparency about data dependencies, though it could mention output format or potential 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?

Two sentences cover purpose, default benchmarks, and fallback behavior. Every word is necessary; no fluff. Efficient and well-structured.

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 description explains the tool's mechanism but does not describe the output format or what the agent can expect as a result. Since no output schema exists, the description should fill that gap, which it does not.

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 100%, so baseline is 3. The description adds no new parameter-level meaning beyond what the schema already provides (defaults are stated in schema). The fallback behavior is tool-level context, not parameter-specific.

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 compares portfolio return against benchmark indices, specifying default benchmarks (SPY and QQQ). It effectively distinguishes from sibling tools like show_portfolio or show_risk by focusing on benchmark comparison.

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 explains how the tool operates (snapshot-based or fallback) but does not explicitly state when to use it over alternatives or when not to use it. The purpose is clear, but guidance on context is lacking.

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