Dashas: Sthira Mahadasha

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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the bar is lower; the description nonetheless adds real behavioral context — how the seed (Brahma planet) is derived, the 7/8/9-year duration rules, the equal 12-fold sub-period split, and the exact sidereal year basis (365.256364d). It also advertises the 20-credit Tier 2 cost, which annotations do not cover.

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?

Dense but front-loaded: system identity first, then seed derivation, durations, sub-period rule, and year basis, followed by grouping/endpoint/cost metadata. Every sentence carries computational information; only the parenthetical PyJHora internals border on excessive for an agent caller.

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?

The tool is a deterministic calculation, an output schema exists, and the description supplies the algorithmic rules (seed selection, direction, durations, year length) an agent would need to interpret or sanity-check the result. Nothing material is missing for correct invocation.

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?

Only one top-level parameter (body) and schema coverage is 100%, so the baseline is 3. The description says nothing about the birth-data fields or the optional targetDate/targetTime/targetTzOffset overrides, which the schema also leaves thinly explained — a missed opportunity but not a gap in required input semantics.

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 system ('Sthira Dasha: Jaimini fixed rasi-dasha') and describes exactly what the tool computes: a 12-sign forward walk with per-sign durations and a 12-fold sub-period split. It does not explicitly distinguish itself from the sibling levels (sthira_antar, sthira_pratyantar, sthira_sookshma), leaving the mahadasha scope to be inferred from the name and the 'MD walks 12 signs' phrasing.

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?

No statement of when to choose Sthira over the many other dasha systems (Vimshottari, Chara, Yogini, etc.) or over the sthira sub-period siblings. The agent must already know Jaimini terminology to know this is the top-level rasi dasha, and the description offers no routing guidance.

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