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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, but the description adds significant behavioral context: graceful handling of 403 by returning a warning structure, data integrity cross-checking for mass zeroing, and explicit instruction to treat suspect_zeroed balances as unavailable rather than real R$0. This goes well beyond what annotations provide.

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 front-loaded with the core purpose, then provides a detailed data integrity warning and bulk support note. It is somewhat long but information-dense; each sentence adds value, though the data integrity section could be condensed without losing essential guidance.

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 complex tool with no output schema, the description covers return structure, error handling, data integrity, and bulk execution. However, it lacks parameter semantics and explicit alternative-tool guidance, leaving some usage gaps.

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 0%, so the description must compensate, but it only mentions item_ids for bulk execution. Parameters like item, page, type, item_id, and page_size are left unexplained, with no details on filtering or pagination semantics.

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 uses the specific verb 'Returns' and identifies the resource as 'investment portfolio for a connection', enumerating asset types (FIIs, stocks, ETFs, fixed income, mutual funds, retirement, COE). This clearly distinguishes it from sibling tools like openfinance_list_investment_transactions, which focus on transactions rather than the portfolio.

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?

Provides clear context by specifying that it targets connections with the INVESTMENTS product enabled and notes bulk execution via item_ids. However, it does not explicitly mention alternatives or when to use list_investment_transactions instead, so it lacks explicit exclusions.

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