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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false), lowering the bar. The description adds useful output-shape context — the specific score, kootas and dosha reporting — which compensates for the missing output 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?

Front-loaded with the core purpose and output summary, then the trigger phrases. One dense sentence plus a short usage list; every element earns its place, though the output enumeration is fairly packed.

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 no output schema and a nested two-person input, the description compensates well by enumerating the returned artifacts (36-point score, 8 kootas, doshas, cancellations). An agent knows what it will get back and what inputs are required.

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 100% and both parameters (person_a, person_b) are fully documented with nested field descriptions, so the schema carries the burden. The description adds no syntax or format detail beyond what the schema provides, making the baseline 3 correct.

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?

States a specific verb and resource — marriage compatibility of two people from birth details — and enumerates the exact outputs (Ashtakoot Guna Milan out of 36, 8 kootas, Nadi/Bhakoot dosha, Mangal dosha). It is clearly distinct from read_kundli and life_timing, though it does not name those siblings explicitly.

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?

Provides concrete trigger phrases ('match me with my partner', 'kundli milan', 'are we compatible') that map natural user requests to this tool. No exclusions or explicit when-not-to-use guidance, but the context is unambiguous.

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