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

The description adds value beyond annotations by stating 'No hidden fees, no upsells' and clarifying that Xpert Assist is not a line-by-line review, which prevents misuse. Annotations already cover read-only/idempotent safety, and the description supplements with output-facing promises.

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, followed by useful scope and behavioral details. Every sentence serves a purpose, especially the nuanced Xpert Assist clarification, without redundant filler. It balances completeness with conciseness.

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 read-only cost calculator with extensive annotations and schema coverage, the description covers all critical user-facing aspects: what it returns, the service tiers, business types, and the precise nature of Xpert Assist. No output schema exists, but the description explains the return format (itemized price breakdown) sufficiently.

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?

With 100% schema coverage, the baseline is 3, but the description adds semantic meaning by mapping service tiers (DIY, Xpert Assist, Full Service) to parameters like wants_expert_help and wants_full_service, and clarifying that Xpert Assist includes expert guidance but not full preparation. This goes beyond the schema's basic descriptions.

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 opens with 'Shows exactly what it costs to file a tax return with TaxAct' and specifies an itemized price breakdown, clearly identifying the tool's purpose. It explicitly differentiates from siblings like estimate_taxes by focusing on actual filing costs, and covers specific service types and business entities.

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 clearly scopes when to use the tool by covering DIY, Xpert Assist, and Full Service for consumer and business returns, and provides explicit presentation guidance for Xpert Assist. However, it does not explicitly name alternative tools (e.g., estimate_taxes) or exclusions, so it misses 'when-not-to-use' guidance.

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