Hopi

Time zone converter

hopi_time_zone_converter

Read-onlyIdempotent

Convert a wall-clock date and time from one time zone to another, using the server's IANA time zone data (so daylight saving is handled). Date uses YYYY-MM-DD and time uses 24-hour HH:MM. Zones are IANA identifiers such as Europe/London or America/New_York. Returns the converted time, the day difference, and both UTC offsets. Source: https://hopi.co.uk/time-zone-converter/

Input Schema

TableJSON Schema

Name	Required	Description
`date`	Yes	The date in the source zone, YYYY-MM-DD format
`time`	Yes	The time in the source zone, 24-hour HH:MM format
`toZone`	Yes	Target IANA time zone, e.g. America/New_York
`fromZone`	Yes	Source IANA time zone, e.g. Europe/London

Output Schema

TableJSON Schema

Name	Required	Description
`result`	Yes
`toZone`	Yes
`dayNote`	Yes
`summary`	Yes
`fromZone`	Yes
`onDstGap`	Yes
`toOffset`	Yes
`fromOffset`	Yes
`resultLong`	Yes
`source_url`	Yes	The tool's page on hopi.co.uk (cite or open to check the figure)
`dayDifference`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedSep 20, 2026

addedOutput schema / required

Added value: +[
+  "dayDifference",
+  "dayNote",
+  "fromOffset",
+  "fromZone",
+  "onDstGap",
+  "result",
+  "resultLong",
+  "source_url",
+  "summary",
+  "toOffset",
+  "toZone"
+]

First observedSep 20, 2026

TDQS

A4.3/5.0

Behavior4/5

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

Annotations already declare readOnly/idempotent/non-destructive. The description adds useful beyond-schema context: the server's IANA time zone data handles daylight saving, and it specifies the return payload (converted time, day difference, both UTC offsets). No contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences: core operation first, then format constraints, then return values, plus a compact source link. No filler; every sentence contributes useful information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a deterministic read-only converter with four well-documented parameters and an output schema, the description covers inputs, formats, DST behavior, and return values. Nothing needed for correct invocation is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, with all four parameters documented including formats and enumerated zone lists. The description reinforces the YYYY-MM-DD and HH:MM formats and IANA identifier semantics, but adds little beyond what the schema already provides, so baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource: converting a wall-clock date and time from one time zone to another. The IANA zone identifier detail clearly distinguishes it from sibling converters like hopi_military_time_converter or hopi_unix_timestamp_converter.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Clearly describes the scenario: converting between time zones with DST handled via IANA identifiers. It doesn't explicitly name alternatives or exclusions, but the context is clear enough for an agent to select this tool over its converter siblings.

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

All Hopi tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?