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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so basic safety and idempotency are covered. The description adds value by disclosing output components (common securities, portfolio percentages, weighted overlap, identifier lineage) and explicit caveats ('as-filed public data, not live holdings or investment advice'), but it does not cover potential rate limits, authentication needs, or data update frequency.

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?

Two sentences, front-loaded with the core action and scope, followed by a list of returned artifacts and a caveat. No waste; every phrase is informative.

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 no output schema and only three parameters, the description is quite complete: it enumerates the main outputs and includes caveats about data freshness and intended use. However, it could be more complete with guidance on handling identical funds or error cases, but that is minor.

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 the schema fully documents all parameters (fund_a, fund_b, limit). The description does not add any additional parameter semantics beyond what the schema provides; baseline 3 is appropriate when the schema does the heavy lifting.

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?

States a specific verb and resource ('Compare two funds in the same self-hosted SEC Form N-PORT snapshot') and specifies the scope (same snapshot). This clearly differentiates it from nport_fund_holdings and other financial siblings like stock_compare or crypto_compare by anchoring to N-PORT data.

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 explicit guidance on when to use this tool versus alternatives such as nport_fund_holdings, stock_compare, or other comparison tools. It only states what the tool does, leaving the agent to infer the use case (e.g., fund overlap analysis) without any when/when-not conditions.

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