trading_calendar

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

With no annotations, the description must carry the full burden. It adds minimal behavioral specifics beyond the name: 'including holidays and early closes' is useful, but it omits details like date range filtering (start/end parameters), return fields, or whether sessions are weekdays only. This is thin coverage for its safety and behavior profile.

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?

A single, front-loaded sentence that states the verb and resource without any unnecessary words. It is appropriately concise for the tool's simplicity, though it lacks parameter information (captured elsewhere).

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?

The description is incomplete for a tool with two optional parameters and no schema descriptions. It does not explain how start/end affect the output, what 'sessions' includes (dates, times, status), or how to interpret results. The presence of an output schema partially covers return structure, but the description still leaves critical usage gaps.

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 0% and the description does not mention the 'start' and 'end' parameters at all. There is no guidance on their meaning, format, or whether they are optional filters. This is a complete lack of parameter documentation, forcing the agent to guess from the parameter names alone.

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 'List NYSE sessions, including holidays and early closes' clearly states a specific action (list) and resource (NYSE sessions), and includes a distinctive detail (holidays/early closes). This unambiguously differentiates it from sibling tools like market_bars or market_status.

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 does not explicitly state when to use vs. alternatives, but the purpose is clear enough that an agent can infer it should be used for obtaining trading session dates. There is no mention of exclusions or alternative tools, which prevents a higher score.

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