get_prayer_times_today

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It does state the return timezone (MYT, UTC+8), which is useful. However, it doesn't disclose what fields the response contains, whether zone validity is checked, or error behavior for invalid zones. The timezone disclosure is genuinely helpful context.

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?

Three sentences, zero waste. Each sentence serves a purpose: defining the scope (today, zone), specifying zone format, and clarifying timezone. Exceptionally tight and front-loaded.

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 tool is simple (1 required param) with an output schema present, so the description doesn't need to explain return format. It covers the zone format and timezone semantics. It's slightly incomplete regarding validation behavior and whether open-ended zones are accepted vs only those from list_zones, but for a single-param tool with output schema this is adequate.

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%, so the description must compensate for the zone parameter. It does explain the zone format (JAKIM, e.g. SGR01, WLY01) and gives examples, which adds real meaning beyond the schema. However, it doesn't indicate whether the zone must map to a listed zone from list_zones, which would be useful given that sibling tool exists.

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 states the verb+resource (get prayer times for today) and scopes it to 'today' in 'the given zone'. It distinguishes from siblings by highlighting the 'today' scope vs get_prayer_times_month. However, it doesn't explicitly differentiate from get_next_prayer, so it loses a point.

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 implicitly conveys usage by scoping to 'today' and a specific zone format, which differentiates it from the month tool. However, there are no explicit when-to-use or exclusion statements, nor mention of when get_next_prayer or list_zones would be preferable. The zone code format note (JAKIM) is helpful context.

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