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

No annotations, so the description carries the burden and does well: it discloses the conditional degradation without time, the chart_id round-trip, and the input_conflict error behavior. It omits permissions/rate-limit context, but for a stateless computation tool that is minor.

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?

Dense, front-loaded sentences: output summary first, then input guidance, then mode options, then the chart_id/error contract. No filler.

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?

With an output schema present, return-value detail is rightly omitted, and core usage is covered. But for an 11-parameter tool with near-zero schema descriptions, the unexplained ayanamsa and house_system enums leave the agent guessing about meaningful inputs.

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 only 9% across 11 params, so the description must compensate. It explains date/time, place/geonameid, detail, and chart_id, but leaves ayanamsa, house_system, lang, podrobno, and utc_offset unexplained, so coverage is only partial.

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?

Names the specific resource (натальная карта / jyotish) and enumerates its outputs (grahas by sign/house, lagna, Moon nakshatra, current dasha), so an agent knows what it computes. It does not explicitly contrast itself with siblings like varga_chart or chart_transits, but the resource is distinctive.

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?

Gives concrete conditions: place OR geonameid, time optional with the exact consequence of omitting it (no lagna/houses/dashas), and reuse of chart_id instead of date/time/place. It even flags that supplying a conflicting field yields input_conflict. It just doesn't name alternative tools for adjacent needs.

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