portfolio_get_performance

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It implies a read-only operation through 'Get' but does not state whether it is safe, what data is returned, whether a portfolio must already exist, or any other behavioral traits. This is a significant gap for a tool with no annotations.

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, clear sentence that gets to the point without extra words. It is appropriately sized for a simple getter, though it lacks any structured breakdown or expanded explanation that could aid an agent.

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 there is no output schema and no annotations, the description fails to explain what the returned performance data looks like, how the 'period' parameter affects the output, or how this tool differs from siblings like portfolio_get_summary. The description is too thin to be fully complete for an agent selecting among many similar portfolio tools.

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 description coverage is 100% since both parameters are described. The baseline is therefore 3. The description adds no additional parameter semantics beyond what the schema provides, but the schema already documents 'portfolioId' and 'period' with an enum for period.

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 action ('Get') and resource ('portfolio performance') with a time dimension ('over time'). However, it does not distinguish itself from sibling tools like portfolio_get_summary or calculate_portfolio_allocation, so it lacks sibling differentiation.

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 provides no guidance on when to use this tool versus alternatives. It does not mention exclusions, prerequisites, or comparisons to similar portfolio-related tools. The user is left to infer usage from the name alone.

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