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

Annotations cover safety (readOnlyHint=false, non-destructive, non-idempotent), and the description adds material context beyond them: the premium credit cost (5,000 / Tier 7 / ~50% of free monthly budget) and the required user confirmation. It also discloses the scoring methodology and that it is a rendering operation. A minor gap is the '?format=html' query-string reference that has no matching schema parameter, which slightly muddies how the format is actually selected.

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 most important sentence first, then methodology, then the activity pointer and format note; the bracketed metadata stays compact. No wasted prose, though the methodology sentence is denser than strictly needed for tool selection.

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?

An output schema exists, so return values needn't be described, and the cost/confirmation warning covers the highest-risk behavior. However, with 13 parameters at 31% schema coverage, the description leaves a genuine documentation gap for an agent trying to populate the optional inputs correctly.

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 only 31% across 13 parameters, so the description must compensate — but it only addresses `activity` (already enumerated in the schema) and gestures at the shared window-scan engine. topN, language, latitude, longitude, ayanamsaId, search_window_start/end and the whitelabel toggle are left entirely to the schema, which is thin here.

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 (Render) and resource (standard A4 report of most auspicious dates for a chosen activity over a search window), and explicitly contrasts with the /vedic/muhurat/* engine family. An agent can tell this is the report-rendering variant rather than a data endpoint without opening the schema.

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?

Points to /muhurta/types for the valid activity list, notes the PDF/HTML output toggle, and the cost block instructs 'Confirm with user before invoking' — real when-to-use guidance. It stops short of an explicit when-not or a named alternative report tool, so 4 rather than 5.

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