All market statuses

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

Annotations already indicate readOnlyHint=true and openWorldHint=true, so the description need not cover safety. It adds 'snapshot' implying point-in-time data, but no other behavioral traits (e.g., freshness, rate limits). No contradiction.

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?

Single sentence, front-loaded with key information: what the tool does and its scope. No wasted words.

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?

Tool is simple with 1 optional param, no output schema, and no nested objects. Annotations cover safety and variability. The description is adequate to understand what the tool returns and its basic behavior.

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 description coverage is 100%, so the schema already documents the region parameter with valid values. The description does not add additional param meaning beyond 'snapshot for every market,' 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 'Open/closed snapshot for every market' clearly states the tool returns status for all markets, distinguishing it from sibling tools like 'markets_status' (likely a single market) and 'markets_hours' (likely trading hours). The name and title reinforce this specificity.

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?

No guidance on when to use this tool versus alternatives. The optional region parameter is not contextualized (e.g., when to apply a filter). Sibling tools exist, but no when-to-use or when-not-to-use advice is given.

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