get_four_pillars

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the 'fixed late-zi rule' but does not explain what that entails, nor does it address timezone handling, edge cases, or return format. The phrase 'exact civil-time' hints at precision but omits critical behavioral details needed for safe usage.

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, front-loaded sentence that directly states the tool's purpose and rule. It contains no redundant words and earns its place, though it is brief. The structure is efficient and easy to parse.

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?

This tool has a moderate complexity (four-pillar calculation), but the description does not explain what 'four pillars' are, how the fixed late-zi rule is applied, or what the output looks like. With no output schema and no annotations, the agent is left without enough context to confidently invoke the tool correctly. The description is too minimal for the task.

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 input schema has 0% description coverage, and the description does not compensate by explaining the parameters 'timezone' and 'local_datetime'. While the parameter names are self-explanatory to some degree, the description adds no information about their relationship or the 'fixed late-zi rule' in context, failing to help the agent understand required inputs.

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 clearly identifies the tool's function: returning exact civil-time four pillars using a specific rule ('fixed late-zi rule'). The verb 'return' and resource 'four pillars' are explicit and distinguish it from siblings like 'get_day_pillars' or 'get_calendar_context' by specifying a unique calculation method.

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 implies usage for exact civil-time calculations with a particular rule, but it does not explicitly state when to use this tool versus alternatives such as 'get_day_pillars'. There are no exclusions or mention of alternative tools, leaving the agent to infer context from the rule mention alone.

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