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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, openWorldHint=false, so safety and determinism are covered structurally. The description usefully adds that output is interpretive 'windows' rather than a deterministic prediction, which shapes how an agent should present results, but it says nothing about computational cost, required chart inputs, or failure modes when birth data is inconsistent.

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?

Two sentences, zero filler, with the operative technique front-loaded and the interpretive caveat second. Nothing could be cut without losing information.

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-value shape needn't be described. However, for a 10-parameter tool with 0% schema coverage and no usage guidance, the description leaves significant gaps around required birth data, the location input branch, and the time-horizon parameter.

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 0% across 10 parameters, so the description carries the full explanatory burden and does not compensate. It never clarifies birth-data fields (name/date/time/place), the place-vs-latitude/longitude/timezone anyOf branch, the horizon control 'years' (0.25–20, default 5), or 'startDate'/'timezoneOffset'.

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 names a specific verb (finds overlaps) plus the exact astrological technique (Jupiter transiting the natal seventh sign intersected with Venus/seventh-lord Vimshottari periods). That technique-level specificity cleanly separates it from siblings such as analyze_marriage_structure, get_marriage_readiness, or find_muhurta, so an agent can route to it without opening schemas.

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?

The second sentence is a scope/liability caveat ('returns planning windows, never a guaranteed marriage prediction'), not usage guidance. There is no statement of when to prefer this over get_marriage_readiness, analyze_marriage_structure, or fuse_timing, and no prerequisites such as requiring an already-computed natal chart.

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