get_portfolio_history

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

Annotations already declare readOnlyHint=true, so the description adds value by disclosing that it is premium-gated and requires a specific API key. This goes beyond the annotations by providing authentication and access control details. No contradictions.

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 with three sentences, each adding essential information: purpose, premium gating, and API key requirement. There is no wasted text.

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 simple read-only tool with one parameter and no output schema, the description adequately covers purpose and access requirements. It could be improved by hinting at the return format, but the current description is sufficient for an AI agent to understand the tool's basic behavior.

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% (one parameter 'days' with a description), so the baseline is 3. The tool description does not add any additional meaning beyond what the schema already provides for the parameters.

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 'Get portfolio value history' which includes a specific verb and resource. It distinguishes itself from sibling tools like get_portfolio_breakdown and get_portfolio_summary by focusing on history. The additional context about premium gating also helps clarify its 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 description mentions that the tool is premium-gated and requires the 'IWMM_API_KEY', providing clear context for when it can be used. However, it does not explicitly state when to use this tool versus alternatives or provide exclusions, which prevents a higher score.

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