get_ticker

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

The description explicitly marks the tool as read-only and lists the main return fields, which is helpful given no annotations. However, it does not disclose potential rate limits, error conditions, or other behavioral details that could affect invocation.

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 concise with two sentences and a bulleted list. It front-loads the purpose and read-only nature, then efficiently adds parameter examples and return value details with no redundant text.

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 simple ticker tool, the description adequately covers purpose, parameters, and return values despite lacking an output schema. It does not address error handling or limitations, but the core information is present and actionable.

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 sole parameter product_code has a default but no schema description. The tool description compensates by providing specific examples (FX_BTC_JPY, BTC_JPY, etc.), adding meaningful context beyond the schema definition.

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 it retrieves the latest ticker from bitFlyer, specifies it is read-only, and lists the main return values. However, it does not explicitly differentiate from sibling tools like get_board or get_executions, though the specific resource ('ticker') implies uniqueness.

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 product code examples but offers no guidance on when to use this tool versus alternatives (e.g., get_board for order book data). There is no mention of context or preconditions for use.

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