Parse an ISO date string into year, month, day, hour, minute, and second components for date handling and validation.
Parse an ISO date string and return its components {year, month, day, hour, minute, second}.
| Name | Required | Description | Default |
|---|---|---|---|
| date_string | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v1.0.4Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden. It discloses the input format (ISO) and the exact output shape, which for a pure, side-effect-free conversion is meaningful. However it omits error behavior for invalid strings and any timezone/offset handling, which are the main behavioral unknowns.
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 pairs the action with the exact return contract. Every clause earns its place with no filler.
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?
An output schema exists, so return-value explanation is largely redundant but harmless. For a one-param pure utility the definition is nearly complete, but missing error-handling notes for non-ISO input leaves a gap an agent might care about.
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 coverage is 0% (the lone parameter is described only as 'string'). The description compensates by specifying the parameter must be an 'ISO date string', adding format semantics the schema lacks. Baseline 3 for a single-parameter tool whose schema already names the field.
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?
States a specific verb ('parse'), a specific resource ('ISO date string'), and the exact return shape ({year, month, day, hour, minute, second}). This clearly distinguishes it from siblings like datetime_format. No explicit sibling differentiation in wording, but the verb+resource is unambiguous.
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 versus datetime_format, datetime_diff, or other datetime siblings. Nothing says what happens on malformed input or how it relates to the formatting counterpart. Usage must be inferred from the name alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.