Timestamp convert

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

Annotations already declare readOnly, idempotent, closed-world behavior, so the bar is lower; the description still adds real context — digit-count auto-detection of units, the server's UTC as the default timezone, and the now-default behavior. It says nothing about invalid-input handling or whether ambiguous timestamps fail, which would be the remaining behavioral gap.

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?

One dense paragraph with the primary behavior front-loaded and no padding sentences; each clause covers a distinct capability. It is slightly cramped — parsing the output-format list takes effort — and the trailing web-version URL adds little for an agent.

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?

There is no output schema, and the description compensates fully by enumerating every returned representation (ISO 8601 UTC/zoned, RFC 7231, local offset, relative time, day of year, ISO week, Unix s/ms). Combined with the annotation profile and 100% schema coverage, nothing essential for correct invocation is missing.

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 100%, so baseline is 3; the description earns an extra point by explaining the auto-detect rule ('from the number of digits') for `unit` and the coupling between wall-clock `value` input and the `timezone` parameter, neither of which the schema spells out. It treats `zones` only as 'world clock' without noting the 50-item cap beyond 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?

States a specific verb (convert) and resource (Unix timestamp / date string) and enumerates the output formats produced, so an agent knows exactly what it returns. The closing clause 'Date arithmetic is not done here' actively separates it from siblings like calc_date_diff and calc_due_date.

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?

Gives clear conditions: 'No value = now' for a quick current-time lookup, a wall-clock string without an offset is interpreted in "timezone", and date arithmetic belongs elsewhere. It never names the specific sibling tools to use instead for arithmetic, which keeps this below a 5.

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