getCoinOHLCVToday

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

With no annotations, the description carries the behavioral burden and does add real value: read-only, no API key required, and the important caveat that the candle is still in progress (so values can change). It stops short of describing the returned fields or any rate/coverage limits.

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?

Four short sentences, front-loaded with the purpose, then routing, then prerequisite. Nothing is redundant or padded.

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 two-parameter read tool with no output schema, the description covers purpose, alternatives, freshness semantics, and the id-resolution requirement. Only minor gap is not indicating the shape of the returned candle (open/high/low/close/volume, timestamp).

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% and the coinId description already explains the 'symbol-name' slug format and that it is not derivable from the ticker. The description's note about resolveId largely restates the schema, and the 'quote' parameter is never mentioned outside the schema.

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 — the in-progress OHLC candle for today — and immediately separates it from getCoinOHLCVLatest, getCoinOHLCVHistorical, and getTickersById. An agent can pick this tool without opening any 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 a concrete use case ('today's high and low for ETH') plus explicit routing: spot price goes to getTickersById, past candles to getCoinOHLCVHistorical. It also states the prerequisite that coinId must first be resolved with resolveId.

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