technical_indicators

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered; the description adds that the result is a point-in-time snapshot and that keys are period-suffixed (sma50, rsi14, atr14), which is real behavioral context. It stops short of saying what happens when the period is too short for the slow SMA (error vs. omitted key) or how the values are unit-typed beyond ATR.

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?

Front-loaded with the payload contents, then key naming, then the usage constraint, then the alternative-tool pointer -- roughly five dense sentences with no filler. Every sentence adds information an agent would otherwise have to guess.

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?

Because there is no output schema, the description's enumeration of returned fields and key naming convention does the heavy lifting well, and the sibling pointer closes the main ambiguity. The notable remaining gap is the 'period' string parameter, whose accepted formats are undocumented in both schema and description.

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?

With 0% schema description coverage across 11 parameters, the description must carry the load and only partly does: it maps to the SMA fast/slow pair, the RSI/MACD/Bollinger/ATR groups, and explains the period-embedded key naming. It says nothing about bollinger_k vs bollinger_n, macd_fast/slow/signal roles, the string format of 'period' (default '1y'), or expected ticker format, leaving several parameters undocumented anywhere.

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 artifact (a snapshot of standard technical indicators) and enumerates exactly what it contains: close, two SMAs with distance from price, RSI, MACD, Bollinger bands, ATR in currency and percent, and 52-week high/low with distances. It also distinguishes itself from the sibling custom_analysis, so an agent can pick it without opening the schema.

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 states the routing condition explicitly: for custom indicators, expressions, conditions, or a chart, use custom_analysis instead. It also gives a positive usage constraint -- the requested period must be long enough for the slow SMA -- which is precisely the kind of precondition an agent would otherwise get wrong.

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