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

With no annotations provided, the description fully carries the behavioral burden. It discloses that the tool counts pre-collected positions rather than calculating charts, that it returns two numbers (matching and indeterminable), and warns that omitting the indeterminable count can understate results by half for the Moon. This goes beyond basic safety and surfaces a critical edge case.

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 compact and front-loaded: purpose first, then clarifying distinction, then parameter enumerations, then a highlighted warning. Every sentence carries meaningful guidance, and the warning about the Moon is placed exactly where it matters.

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 an output schema exists and the tool is moderately complex, the description covers the core behavior, the non-calculation distinction, parameter constraints, and the key edge case. Minor gaps remain: it does not mention the English graha aliases or clarify the lang default, but these are partially recoverable from the schema.

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 coverage is 0%, so the description must compensate. It defines the graha list and the znak range (0–11 with 0 = Aries). However, it omits the English synonyms present in the schema (sun, moon, etc.), potentially confusing an agent into thinking only the Sanskrit forms are valid, and it does not explain the lang parameter beyond what the schema already provides.

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 states exactly what the tool does: count people in the 76k-person corpus with a given graha in a given sign and list known ones. It also explicitly distinguishes itself from chart calculation ('это НЕ расчёт карты'), which separates it from sibling tools like natal_chart and chart_transits.

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?

It gives an explicit when-not-to-use signal: this is not chart calculation, but counting from collected positions. It also warns about the Moon ambiguity and clarifies that both matching and indeterminable counts must be reported, guiding correct usage.

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