market_snapshot

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 scope of data (indices, VIX, crypto, FX, commodities) and specific inclusions (^JKSE, USD/IDR). However, it does not explicitly state read-only behavior, data freshness, or any limitations. Since this is a get operation, the risk is low, but the disclosure is minimal.

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 two sentences, front-loaded with the main action and scope. It includes a clear use case without extraneous detail, making it highly concise and well-structured.

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 tool has no parameters and an output schema exists, the description adequately covers the tool's purpose and scope. It mentions specific assets and a use case, which is complete for a low-complexity snapshot 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 tool has zero parameters, so schema coverage is trivially 100%. The baseline for 0 parameters is 4, and the description appropriately does not need to explain any parameters.

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 states 'Get a cross-market overview: US and Asian indices, VIX, crypto, FX and commodities' with a specific verb and resource. It clearly distinguishes from sibling tools like get_price or get_prices by emphasizing a market-wide snapshot rather than a single symbol query.

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 says 'Use this to answer "how are markets doing" without picking symbols by hand', providing a clear when-to-use context. It implies an alternative approach (manually selecting symbols) but does not name specific sibling tools, so it stops short of a 5.

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