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

Adds substantial context beyond the readOnly and openWorld annotations: the possible candle sources including Binance.US, Kraken, Gate, MEXC and the XRP Ledger DEX, the dollar-quote substitution behavior, and a 60-calls-per-hour rate limit. It also clearly disclaims candle fetching and signal generation, which prevents a common misuse.

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 pricing context is front-loaded and the exclusion and rate limit are placed where an agent will see them. It is dense but every clause carries useful information; slightly more separation between the exchange list and the interval statement would improve scanability.

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 free lookup tool with a full output schema and annotations, this is complete: it covers supported pair sources, quote substitution, excluded capabilities, the sibling alternative, and the rate limit. Nothing needed to call it correctly appears to be missing.

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 accepted pair formats well. The description still adds meaning by explaining that another dollar quote such as USDT, USD or USDC can stand in for the requested quote, which is resolution behavior the schema does not state.

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: checks whether a crypto pair is supported, which exchange supplies its candles, and which intervals the paid tools accept. It explicitly separates itself from sibling ichimoku_trend and from the paid tools, so an agent can choose it without opening another 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?

Gives an explicit use condition ("before paying") and names the alternative for a different need ("for the daily trend use ichimoku_trend"). It also states what the tool does not do, fetches no candles and returns no signal, which narrows usage further.

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