prayer_times_for

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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=true and destructiveHint=false, so the safety and idempotency profile is fully covered. The description adds the enumerated return fields, but that content largely overlaps the output schema and adds no auth, rate-limit, or fallback behavior 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, front-loaded with the core purpose, followed by the input constraint and the return contents. No filler. The response-field enumeration is slightly long and partially redundant with the output schema, keeping it short of a 5.

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 values need not be explained. The description covers both input modes and their exclusivity, which is what an agent needs to invoke it correctly. Only the sibling disambiguation against prayer_times_calendar 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 description coverage is 100% (each of the 7 params including method/school IDs is documented), so the baseline is 3. The description goes beyond the schema by stating the mutual-exclusivity rule between city and coordinates, a cross-parameter constraint the schema cannot express, which lifts it above baseline.

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 ('Get') plus resource ('the five daily prayer times') and both supported scopes (UAE city or arbitrary coordinates). An agent immediately knows the operation. It does not, however, distinguish itself from the sibling prayer_times_calendar, which an agent could easily confuse for this tool.

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 a concrete input constraint — 'Pass either a city name OR a latitude+longitude pair, not both' — which is genuine usage guidance. But it offers no when-to-use/when-not guidance relative to alternatives such as prayer_times_calendar, so the routing decision is left to inference.

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