fetch_account_cash

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

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, indicating safe read operation. The description adds value by listing the return fields (free, invested, total, ppl, result, blocked, pieCash), which helps the agent understand the output structure. No contradictions with 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 concise (two short paragraphs) and front-loaded with the main purpose. Every sentence adds value: it states what the tool does, when to use it, mentions siblings, and lists return values with clear labels.

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 parameters and the presence of an output schema (implied by the return field list), the description provides sufficient context for a simple read operation. The account health context and buying power use case complete the picture.

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?

The tool has zero parameters, and the input schema coverage is 100% (void). The description does not need to clarify parameters. It mentions return fields, which is beyond parameter semantics but not a deficiency. Baseline 4 is appropriate for a parameterless tool with full schema coverage.

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 tool retrieves a detailed breakdown of account balance, listing specific components (available cash, invested capital, etc.). It also distinguishes itself from the sibling fetch_portfolio_summary by noting that the sibling provides a richer overview including positions.

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?

Explicitly says when to use: 'check buying power before placing orders' and 'understand the overall account health'. It also directs to an alternative tool (fetch_portfolio_summary) for a more comprehensive view, providing clear guidance on tool selection.

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