Crypto ticker (OKX)

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so safety is clear. Description adds value by specifying exact data returned (fields like bid/ask, 24h stats). No contradictions.

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?

Two concise sentences with no fluff. Front-loaded with the purpose and key fields. Every sentence earns its place.

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?

Given simple schema, no output schema, and strong annotations, the description covers all essential information: what it returns, input format, and supported instrument types. Complete for a straightforward 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?

Single parameter instId with schema description providing examples (BTC-USDT, BTC-USDT-SWAP). Schema coverage is 100%, and description adds no extra meaning beyond schema, but baseline is high. No ambiguity.

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?

Description clearly states the tool returns latest ticker for one instrument with specific fields (last price, 24h high/low/volume, bid/ask). It differentiates from sibling tools like crypto_all_tickers by specifying it's for a single instrument.

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?

Explicitly states 'Works for spot and swap ids', guiding valid input formats. While not explicitly stating when not to use, context with siblings implies for a single instrument ticker; for all tickers use crypto_all_tickers. Good implicit guidance.

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