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

Annotations declare readOnlyHint and destructiveHint, so safety is covered. The description adds that no key is required, that it defaults to today, and that daily readings are excluded due to licensing. This provides useful context beyond annotations.

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 short sentences with essential information front-loaded. No redundancy, every clause adds value.

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 read-only tool with one optional parameter and no output schema, the description covers return values, default behavior, exclusions, and authentication. It is fully sufficient given the low complexity.

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 covers the single 'date' parameter with format, pattern, examples, and description. The tool description repeats the default-to-today behavior but adds no new meaning beyond the schema. With 100% schema coverage, baseline 3 applies.

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?

Description explicitly states the verb 'Get' and the specific resource: Western liturgical season, color, RCL year, and major feast for a date. It clearly differentiates from siblings like get_sermon or get_verse by focusing on liturgical calendar data.

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?

States 'Useful for date-aware, season-appropriate faith content' which gives context. Excludes daily readings with the note about licensing, implicitly steering users elsewhere for readings. However, it doesn't name specific alternative tools, so not a 5.

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