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

The readOnlyHint annotation already covers the safety profile, so the description's remaining job is added context; it usefully discloses the default time window (upcoming unless changed) but says nothing about pagination behavior or result size. That default-scope note is genuine value, but the disclosure is thin overall.

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, default scope front-loaded, use cases second, API endpoint last. No filler, no repetition of schema content in bulk.

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?

With no output schema, the description is the right place to frame return usage, and it does so via the question/field mapping; annotations cover read-only safety. The only meaningful gap is any note on paging through large result sets, which is left entirely to the schema.

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 the baseline is 3. The description's gloss on fields (volunteers = the roster, plans = order of service) largely restates the schema enum descriptions and adds no syntax or interaction detail beyond it.

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+resource ('List services') and clarifies the default scope ('upcoming by default'), so an agent knows exactly what comes back. It does not name or distinguish itself from sibling elvanto_get_service, so it falls short of the 5 bar for sibling differentiation.

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 concrete triggering questions ('who is serving Sunday?', 'what are we singing?') and ties them to specific fields to request, which is clear when-to-use context. It offers no exclusions or pointer to get_service for a single service, so it stops short of explicit alternatives.

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