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

Annotations already declare readOnly, idempotent, non-destructive and non-open-world, so the safety profile is covered. The description goes beyond them by spelling out the return contents (verdict, near window, strongest month, planet reason, remedy, 12-month tone bar), which is valuable given there is no output schema. It does not discuss determinism of results or cost, hence not a 5.

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, front-loaded with what gets timed, then returns, then the usage trigger. The middle clause packs a long return list and topic glosses, which is dense but every element carries information for the caller, so there is little waste.

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 6-parameter tool with no output schema, the description covers purpose, topic vocabulary, expected outputs and the trigger phrasing, so an agent has enough to invoke it correctly. Minor gaps remain (no explicit guidance on how birth_time absence affects results beyond the schema's own note, no exclusions), keeping it from a 5.

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 the baseline is 3, but the description adds real meaning to several enum values the schema lists only by name: 'money (career and income)', 'abroad (travel and settling overseas)', 'job (job change)', and 'sade-sati (Saturn phase and when it ends)'. That glossing helps an agent pick the right topic, which is the one call that most affects the result, though the remaining params (name, gender, birth_*) are left to the schema.

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 states a specific verb+resource ('Times one life question from the Vedic chart') and enumerates the exact topics it handles, so its scope is unambiguous. It never names the siblings match_kundli or read_kundli to draw the boundary, so it falls just short of the top mark, but the distinct 'timing' purpose is easy to separate from chart-reading or matching tools.

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?

It gives an explicit trigger: 'Use for "when will I…" or "will I…" questions,' which cleanly maps user phrasing onto this tool. It offers no when-not conditions and no named alternative for adjacent cases (e.g. reading a chart vs timing a question), so it stops short of a 5.

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