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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the bar is lower; the description still adds genuine behavior: the natal chart and dasha/transit scan are computed once and shared, the `level` default differs from the per-area routes (antar), and the call costs 100 credits at Tier 4. Response shape is covered by the output schema, so nothing critical is 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?

Three front-loaded sentences with the scope first, then the shared-computation model, then the default caveat; the bracketed group/endpoint/cost lines are compact and useful. Nothing is padded, though the middleware metadata lines are boilerplate rather than prose.

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 batch aggregator over six sibling routes, the description covers scope, sharing behavior, the divergent default, and cost, while the rich schema and output schema handle input and return details. An agent has enough to choose it over the single-area tools and to call it with correct expectation of response size.

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 100%, so baseline is 3. The description restates what the schema already documents (the `areas` subset and the antar default) without adding new semantics such as how `minScore` or `years` interact with merged area blocks.

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 resource and scope precisely ('All six life areas in one call') and enumerates them, so an agent can distinguish it from the six single-area siblings (astroway_vedic_timing_marriage, _career, etc.) without opening a schema. It even states the relationship: each area block equals its own /vedic/timing/{area} route.

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?

Implies when to use it — one call instead of six area calls, or a subset via `areas` — and explains the `level` default is chosen 'to keep the response small', which is a real selection tradeoff. It stops short of an explicit exclusion (e.g. 'for a single area, use the per-area route to avoid the merged payload') and doesn't compare its 100-credit cost against running six cheaper calls.

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