Plan to add a person to a ChurchTools group

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

It discloses behavior that annotations do not: the call is side-effect-free (it produces a plan, not a write), that an already-member person is an error, and where valid role ids originate. The annotations only carry readOnlyHint=false, destructiveHint=false and openWorldHint=true, which do not convey any of that. The one gap is that it never states whether the plan expires or whether re-calling is idempotent.

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 zero filler, and the highest-value fact (writes nothing, returns a plan) is front-loaded before the error condition and the role-id source. Nothing here restates the name or title.

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 six-parameter, no-output-schema tool, it covers the essentials: what the call returns, the failure mode, and where to get a required id. It is not fully complete because it does not connect the plan to ct_execute_plan, leaving the two-step plan/execute workflow implicit.

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 83%, so the baseline is 3, and the description earns above that by explaining the provenance of groupTypeRoleId (GET /groups/{groupId}/roles via ct_api_request) and by framing groupId/personId in terms of the membership being created. It still says nothing about the optional comment, memberStartDate, or groupMemberStatus beyond what the schema already states.

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?

It names a specific verb+resource (add a person to a group) but immediately qualifies the outcome with 'Writes nothing: returns a plan that adds the person', which is the single most important thing to know about this tool. It also distinguishes itself from ct_update_group_member for the already-a-member case, so an agent can separate it from siblings without opening any schema.

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?

The description gives an explicit exclusion ('A person who is already a member is an error; use ct_update_group_member') and a prerequisite for role ids ('Role ids come from GET /groups/{groupId}/roles'). What it omits is the downstream step: it never mentions that the returned plan must be run through ct_execute_plan, which is the natural next action for a sibling tool.

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