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

No annotations exist, so the description carries the burden. It mentions the cost ($0.01) as a behavioral trait, but does not disclose if the tool is read-only, rate limits, or how it handles invalid JSON input.

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 extremely concise: one sentence plus a cost note. No redundant words. Front-loaded with the core functionality.

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 no output schema and limited parameters, the description is too minimal. It does not explain return format, error handling, or time expectations, which is insufficient for a paid 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?

The description says 'from holdings JSON' which aligns with the holdings parameter, but does not add meaning for the api_key parameter (which has no schema description). With 50% schema coverage, the description fails to compensate for the undocumented parameter.

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 calculates total portfolio value in USD from a holdings JSON. This is a specific verb-resource combination that distinguishes it from siblings like get_price or get_summary.

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 includes a cost hint ($0.01) but provides no guidance on when to use this tool versus alternatives (e.g., get_portfolio_health). No when-not-to-use or preconditions are mentioned.

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