market_book_ticker

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

With no annotations, the description carries the full burden. It discloses the lightweight nature and the all-market return when symbol is omitted, but does not mention data freshness, rate limits, or error handling. The description adds some behavioral context beyond the schema, but lacks completeness.

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?

Three sentences, each serving a distinct purpose: stating the core function, comparing to a sibling tool, and clarifying parameter behavior. No redundant or unnecessary words. Highly efficient and front-loaded.

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 simple input schema (single optional parameter) and no output schema, the description adequately covers the tool's purpose and usage. It distinguishes from a sibling tool and explains parameter behavior. However, it does not describe the output structure, which could be helpful for agents. Still, it is fairly complete for a lightweight ticker 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?

Schema coverage is 100%, so baseline is 3. The description explains the symbol parameter's behavior (optionally returns all markets), which is already implied in the schema description. The description adds marginal clarity but does not significantly enhance understanding beyond 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?

Description clearly states it retrieves the best bid and ask price and quantity. It distinguishes itself from the sibling tool market_orderbook by emphasizing it is 10x lighter and covers 95% of use cases. Additionally, it specifies behavior when no symbol is provided (returns all markets).

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 explicitly compares the tool to market_orderbook, stating it is lighter and sufficient for 95% of scenarios. This implies when to use this tool over the orderbook, but does not explicitly state when not to use it or mention other alternatives. Overall, provides clear context for usage.

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