Milli.gold price history

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

Annotations already declare readOnly/idempotent/openWorld, so the safety profile is covered; the description adds real value beyond that with the unit convention (Rial per milligram, with a worked conversion to Toman per gram), the Tehran timezone of the series, and the fact that points are evenly thinned rather than raw. It does not mention freshness/lag or rate limits, but the disclosed constraints are the ones an agent would otherwise get wrong.

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?

Three short sentences, front-loaded with what is returned and followed by the two facts most likely to cause downstream errors. The parenthetical conversion example is slightly verbose but justifies itself as disambiguation between Rial and Toman.

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 no output schema, the description does state the return shape (series with high, low and change) plus units and timezone, which covers what an agent needs to interpret results. It stops short of describing ordering, point timestamps, or how empty/short ranges behave, which is a modest gap for a small read-only tool.

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 both parameters are already fully documented, including the enum meanings and the 2-50 range. The description only echoes points-thinning and timezone, adding little the schema does not already carry; baseline 3 is appropriate.

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: retrieves the Milli.gold 18k gold price *series* over a day/week/month with high, low and change. That clearly separates it from a plain price reader, but the description never names mg_get_price, so the agent must infer the history-vs-current split from the tool name alone.

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?

Usage is implied rather than stated: the period windows make it obvious this is for historical series, but there is no explicit 'use this when you need a trend, use mg_get_price for the current price' routing despite that sibling existing. No exclusions or prerequisites are given.

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