fetchTicker

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions fetching information, implying a read-only operation, but fails to describe critical behaviors such as rate limits, error conditions (e.g., invalid symbols), authentication requirements, or response format. For a tool with no annotation coverage, this leaves significant gaps in understanding how it behaves in practice.

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 a single, efficient sentence that directly states the tool's function without unnecessary words. It is front-loaded with the core action and resource, making it easy to parse quickly. Every part of the sentence contributes essential information, meeting the standard for optimal conciseness.

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 the lack of annotations and output schema, the description is insufficient for a tool that interacts with financial data. It doesn't cover behavioral aspects like error handling or response structure, and while the input schema is well-documented, the overall context for safe and effective use is incomplete. For a fetch operation in a trading environment, more guidance on limitations and outputs is needed.

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 description adds minimal semantic context beyond the input schema, which has 100% coverage with clear descriptions for both parameters. It implies that 'symbol' and 'exchangeId' are used to fetch ticker data, but doesn't elaborate on format constraints or relationships between parameters. Given the high schema coverage, a baseline score of 3 is appropriate, as the schema already documents the parameters adequately.

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 action ('fetch') and resource ('ticker information') with specific scope ('for a symbol on an exchange'), making the purpose immediately understandable. It doesn't explicitly differentiate from sibling tools like 'fetchTickers' (plural) or 'fetchMarkets', but the specificity of 'ticker information for a symbol' provides adequate clarity for basic use.

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 no guidance on when to use this tool versus alternatives like 'fetchTickers' (for multiple symbols) or 'fetchMarkets' (for market data). It states what it does but offers no context about prerequisites, timing, or comparisons with related tools, leaving the agent to infer usage from the name alone.

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