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

The readOnlyHint annotation already establishes that this is a safe read operation. The description adds a useful behavioral detail by noting the statistics are computed from transaction history, but it does not disclose aggregation behavior, output shape, or data limitations beyond what the schema already implies.

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 compact line with no filler. It front-loades the tool's purpose and its computation basis, so every word earns its place.

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?

With no output schema, the description offers only a general sense of what will be returned ('risk and performance statistics'), without specifying the exact metrics or output shape. The read-only annotation and fully described parameters compensate partially, but an agent still lacks enough detail for confident invocation.

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%, so all six optional parameters are already documented with their meanings and defaults. The tool description adds no parameter-level guidance, matching the baseline case where the schema carries the semantic burden.

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 identifies the resource and scope: portfolio risk and performance statistics based on transaction history. It lacks an explicit verb and does not differentiate it from near-siblings like get_portfolio_analytics or get_portfolio_context, so it stops short of a 5.

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?

There is no guidance on when to use this tool versus the many similar portfolio/risk siblings, and no exclusions or prerequisites are mentioned. The only implied context is that transaction history is required, which is not enough to reliably route an agent.

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