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

No annotations are present, so the description carries the full burden. It discloses non-obvious behaviors: 'bin' never 'bir bin', the kuruş part is read separately, and both decimal formats are accepted and disambiguated automatically. It does not describe return shape or error handling, but it adds meaningful behavioral detail beyond the schema.

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 two short paragraphs, front-loaded with the core action and followed by useful Turkish-language rules. The final sentence is slightly promotional ('no off-the-shelf API until now') but still reinforces the use case, so there is minimal waste.

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 tool with no output schema and no annotations, the description should clarify return value and edge-case behavior; it does not. It covers purpose, use cases, and key formatting rules well, but wrapHash behavior and the exact output format remain 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 only 50%, and the description adds valuable amount-format semantics ('1.234,56' and '1,234.56' accepted) beyond the schema. However, currency is only self-evident from its enum values and wrapHash is left completely unexplained, so the description does not fully compensate for the coverage gap.

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 a specific verb and resource: 'Writes a monetary amount out in Turkish words'. It also differentiates the tool from generic libraries by calling out Turkish-specific rules and the invoice/cheque/promissory-note context, making its purpose unmistakable.

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 explicitly frames the tool for invoices, cheques, and promissory notes, and notes it is a mandatory Turkish e-invoice field, giving clear when-to-use context. It does not name alternatives or state when not to use it, but the context is strong enough for selection.

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