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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds one genuine behavioral caveat — Friday times are only included 'where known', warning the agent that data may be incomplete — but says nothing about result ordering, coverage limits, or what happens with an ambiguous location.

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 sentence that front-loads the resource and scope, then the payload contents. No filler, no redundancy, and every clause carries information.

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?

For a simple two-parameter read tool with no output schema, the description covers scope and the main returned fields (addresses, Friday times), which is enough to call it correctly. Minor gaps remain around ambiguous-location handling and result ordering, but nothing essential 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%, so both parameters are fully documented in the schema, which sets the baseline at 3. The description's phrasing 'city, county or metro' restates the schema's own city description rather than adding new meaning, and it says nothing about the limit parameter.

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 names the resource (masjids/mosques), the geographic scope (city, county or metro), and what the records contain (addresses, Friday times where known), so an agent can tell it is a place-lookup tool. It does not explicitly differentiate itself from closely related siblings such as jumuah_times or prayer_times, which keeps it below a 5.

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?

Usage is only implied: an agent can infer this is the tool for finding mosques in an area, and the mention of 'Friday times where known' hints at overlap with jumuah_times. There is no explicit statement of when to use this instead of jumuah_times, khutbahs, or prayer_times, and no prerequisites or exclusions.

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