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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful non-schema context: deprecation status, the sunset date, the stability policy that governs the removal, and the exact replacement path. It does not describe response shape, though an output schema exists to cover that.

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?

The deprecation warning and migration path are front-loaded ahead of the functional description, which is exactly the ordering an agent needs. Sentences are dense and each carries distinct information (sunset date, policy reference, replacement endpoint, varga range); nothing is wasted.

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?

With 100% schema coverage and an output schema, the description need not restate parameters or return values. It covers the two things structured fields cannot convey: deprecation lifecycle and the varga range supported. Only the sibling-selection angle among specialized chart endpoints is left unaddressed.

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 100%, so the schema already documents birth data fields, timezone rules, fields/precision compact mode, and the required format. The description only names the varga range (D1–D60), which is marginal addition over the schema's `varga` property. Baseline 3 is appropriate when the schema does the explanatory work.

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 and resource: 'Calculate a Vedic divisional (varga) chart using sidereal zodiac', and bounds scope with 'Supported vargas: D1–D60'. It distinguishes itself from the new per-varga endpoints, though it does not differentiate from unrelated siblings like astroway_specialized_draconic or astroway_specialized_harmonics.

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?

Gives an explicit migration path and timeline: deprecated in favor of `/vedic/varga/{D1..D60}`, still live until 2027-06-15, then removed. An agent reading this knows to prefer the dedicated endpoints and only fall back here until sunset, but no guidance is offered on choosing between varga and the other specialized-chart tools.

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