get_portfolio_history

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

Discloses access restrictions (premium-gated, 403 for free tier) and auth requirement, but does not describe return format, any limits, or other behavioral traits. Since no annotations exist, the description provides moderate transparency.

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?

Three concise sentences covering purpose, restriction, and requirement. No unnecessary words or redundancies.

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?

Covers the essential aspects: purpose, access condition, auth, and parameter behavior. Absence of output schema is noted but not critical; the tool returns historical values which is implied. Could mention response format but overall complete.

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?

Only parameter 'days' is fully documented in the schema with a clear description. The tool description does not add additional semantic meaning beyond what the schema provides.

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?

Clearly states 'Get portfolio value history' with a specific verb and resource. Implicitly distinguishes from sibling tools like get_portfolio_summary or get_portfolio_breakdown by specifying 'history'.

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?

Mentions that the tool is premium-gated and requires an API key, providing basic usage conditions. However, no explicit guidance on when to use this tool versus alternatives or when not to use it.

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