Plan a new ChurchTools appointment

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

The description asserts 'Writes nothing,' which directly conflicts with readOnlyHint=false, whose meaning is that the tool does modify its environment. This is a mirror of the calibration contradiction case (write verb vs readOnlyHint=true), so the description contradicts the structured annotation.

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 sentence with the key fact ('Writes nothing') front-loaded and no wasted clauses. It is efficient, though the trailing clause about repeatId is slightly compressed.

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 tool whose unusual output is a 'plan' and which has no output schema, the description should explain the plan's shape and how it is consumed. It says a plan is returned but not what it contains or what to do with it, leaving a meaningful gap.

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 all six parameters are already documented, including repeatId's enum-like values in the fields description. The description only restates the single-vs-series distinction, adding no syntax or format detail beyond the schema.

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 description states a specific verb and resource ('returns a plan to create an appointment') and clarifies the default-vs-series scope via repeatId. It implicitly separates itself from the actual write path, but never names the sibling that performs the write (e.g. ct_execute_plan), so sibling differentiation is implied rather than explicit.

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?

By stating 'writes nothing: returns a plan,' it implies this is a first step in a two-phase flow, but it never says when to call this versus ct_execute_plan, nor that execution is required afterward. Usage is left to inference.

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