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

The annotations provide readOnlyHint=true, and the description adds valuable behavioral context: it costs '5 units of the monthly quota' and 'Answers in formatted text.' It also clarifies that it takes no arguments and is a fixed snapshot. While it doesn't discuss failure modes or quota limits, it adds cost and format details beyond what annotations convey, making it informative.

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 description is front-loaded with 'ONE SNAPSHOT OF CRYPTO ONLY, no arguments' and then provides the key details: the top 5 cryptos and score range, usage guidance, cost, and formatting. It is slightly verbose with the phrase 'Use this for a quick picture of crypto alone' but that adds context. Overall, every sentence contributes value without unnecessary fluff.

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 that the tool has zero parameters, a read-only annotation, and no output schema, the description covers all essential information an agent needs to decide whether to call it: purpose, output scope, cost, format, and explicit differentiation from siblings. There are no gaps that would cause an agent to misuse or misselect this 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?

The input schema is empty, and the description explicitly states 'no arguments,' confirming there are no parameters. Since schema coverage is 100% (no properties), the baseline is 3. The description adds the specific output content (top 5 cryptos by score) but that is not parameter semantics. It adequately clarifies that no arguments are needed, which aligns with 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?

The description clearly states the tool provides 'ONE SNAPSHOT OF CRYPTO ONLY' with 'the top 5 cryptos by Martingale Score (0-5) with their Startingale readings.' It names the specific resource (crypto) and the output scope, and explicitly distinguishes it from siblings by pointing to list_top_crypto and market_overview for other needs. This makes the purpose unambiguous and differentiates it from similar tools.

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 explicitly says to use this tool 'for a quick picture of crypto alone' and provides clear alternatives: 'To choose how many or apply a Startingale floor, use list_top_crypto; to cover stocks as well, use market_overview.' This gives direct when-to-use and when-not-to-use guidance, exceeding minimal expectations.

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