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

Annotations already declare readOnly, idempotent, openWorld hints; the description adds valuable behavioral nuance: the coverage limitation (only USDT pairs on Binance/Bybit) and clarifies that absence is about data source, not price existence. This goes beyond repeated annotations and helps set expectations about data availability.

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 sentences, with the core function front-loaded and the coverage caveat placed second. It is efficient and to the point, though the second sentence is a bit long and could be split without loss.

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 should mention return format or structure; it doesn't. However, it does clarify coverage and venue, which are key for correct interpretation. Missing parameter details (limit) and return format make it only partially complete. For a simple read tool, it's adequate but leaves the agent to infer common behavior.

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 0%, so the description must explain the parameters. It mentions 'for an asset' implicitly covering 'symbol', but does not explain 'limit' at all. The description adds minimal value beyond what the schema provides (which only has names and defaults). For a tool with zero coverage, this is a significant gap.

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 clearly states the tool returns daily OHLCV candles for an asset, and adds the venue from which they came. It's specific about the resource (asset) and data type, and distinguishes it from generic time-series tools by mentioning candle granularity and venue.

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?

The description provides a coverage constraint (assets with USDT pair on Binance/Bybit) and explains that absence doesn't mean no price, but it doesn't explicitly mention when to use this tool versus alternatives like get_metric_timeseries. The coverage note implies a selection criterion but doesn't name alternatives or provide when-not-to-use guidance.

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