to_persian_digits

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

With no annotations, the description carries the full burden. 'Any digits' hints that all digit runs in the string are converted, but it does not state whether Arabic-Indic or already-Persian digits are handled, what happens to non-digit characters, or whether the operation is idempotent. For a pure transformer the safety profile is inferable, but the behavioral details are largely missing.

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?

A single front-loaded sentence with no filler. It is appropriately sized, though it is so terse that it leaves nothing to structure beyond the core statement.

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 trivial single-parameter transformer with no output schema, one sentence is close to sufficient, and the return value is self-evident. However, the 0% parameter coverage and the crowded sibling namespace mean the description leaves the agent guessing about scope and edge cases.

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 schema documents only that 'text' is a required string. The description implies the input may contain mixed text and digits but adds no format, length, or encoding details to 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 gives a specific verb and transformation: convert digits in a string to Persian digits. It is clear and unambiguous on its own, but it never differentiates itself from adjacent siblings like number_to_persian_words or price_to_persian_words, which the agent must distinguish by name alone.

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?

There is no guidance on when to use this versus the many sibling conversion tools, no mention of input expectations, and no note about alternatives for whole-number or currency conversion. The agent must infer the use case entirely from the tool name.

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