market_hours

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

No annotations are present, so the description must convey behavioral traits. It does not disclose whether data is real-time or delayed, any caching behavior, or what 'status' entails beyond a vague term. This is insufficient for an agent to understand side effects or reliability.

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 sentence that immediately conveys the action and resource. There is no extraneous information, making it highly concise 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?

Although the tool has no parameters and an output schema exists, the description is minimal. It does not specify what 'market hours and status' includes (e.g., open/closed, pre-market, after-hours). For a tool with many siblings, the context is somewhat incomplete, but acceptable for a simple no-parameter 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, and the input schema is empty. According to the baseline rule, 0 parameters warrants a score of 4. The description adds no parameter details, but none are needed.

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 'Gets current market hours and status,' which specifies the verb ('Gets') and the resource ('current market hours and status'). Among many sibling tools like 'broker_status' and 'session_status', it distinguishes itself as a general market hours tool, though it could be more specific about which market.

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 is provided on when to use this tool versus alternatives like 'schwab_get_market_hours' or 'broker_status'. There is no mention of prerequisites or contextual scenarios.

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