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

Annotations already declare readOnlyHint=true, so the safe-read profile is covered. The description adds real context beyond that: what fields are returned and that members/leaders only appear when fields=["people"] is requested. It does not cover pagination behavior, though the schema documents page/page_size.

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 tight sentence: resource and returned attributes first, then the optional expansion and endpoint reference. No padding or redundancy.

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?

No output schema exists, so the description carries the return-value burden, and it does state the core return shape (groups with meeting day/time/place/frequency). With annotations covering safety and the schema covering all 5 params, nothing an agent needs to call this correctly 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 coverage is 100%, so the baseline is 3. The description adds a concrete, actionable example (fields=["people"] to include members and leaders) that shows parameter intent beyond the schema's field list, which is a modest but real value-add.

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?

Specific verb+resource ('List small groups / ministries') plus the attributes returned (meeting day, time, place, frequency), and it names the underlying endpoint. It is clearly distinguishable from the sibling elvanto_get_group, which fetches a single group.

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 implied rather than stated: it shows how to expand results with fields=["people"], but gives no explicit when-to-use guidance, prerequisites, or named alternatives (e.g. versus get_group or search tools). Adequate but with clear gaps.

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