ct_update_personBuild a preview plan for updating a ChurchTools person, changing only fields whose values differ; set a field to null to clear it.
Writes nothing: returns a plan that patches only the fields whose value changes; null clears a field.
| Name | Required | Description | Default |
|---|---|---|---|
| fields | Yes | The fields to set, e.g. { email: 'a@b.org' } | |
| personId | Yes | The person's id |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds real behavioral value beyond the annotations: it is a dry-run ('writes nothing'), it patches only changed fields, and null clears a field. However, this directly conflicts with the annotation readOnlyHint=false, which declares the tool is NOT read-only, creating an inconsistency about whether the operation has side effects.
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, front-loaded with the most important trait ('Writes nothing'), and every clause (patch-only-changed, null-clears) earns its place. It is very terse for a tool with a nested object parameter and plan/execute workflow, but there is no wasted text.
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 does explain the return value as a 'plan' and describes its patch semantics. But it omits important context for a planning tool: the plan's format and how it is applied (the ct_execute_plan sibling), plus any auth requirements. Adequate but with clear gaps.
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, and the description adds meaning on top: the `fields` object semantics (only changed fields are patched, and a null value clears a field) go beyond the schema's terse 'The fields to set' description. This clarifies how to encode clearing vs. setting.
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 title 'Plan a change to a ChurchTools person' plus the description's 'returns a plan that patches only the fields whose value changes' give a specific verb (plan a patch) and resource (a person's fields). It implies a dry-run/preview distinct from the actual mutation performed by ct_execute_plan, but it never names that sibling, so differentiation is only implicit.
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?
There is no explicit statement of when to use this tool, when not to, or which alternative to choose. The relationship to ct_execute_plan (i.e., that this produces a plan to be executed later) is only inferable from the word 'plan'; the agent gets no routing guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.