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

Annotations supply only destructiveHint=true and a title, so the description does real work here: it discloses the write nature, the Unix-seconds time convention, and the irreversible-without-the-app consequence that justifies the destructive hint. It doesn't cover auth requirements or what the response returns, but the key behavioral risk is surfaced.

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?

Four short sentences, front-loaded with the operation type and the highest-stakes fact (irreversibility), with no padding. Even the API endpoint mapping is a single compact clause that aids provenance.

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 7-param mutation with no output schema and minimal annotations, the description covers operation type, time format, series reuse, and the deletion gap. Missing only peripheral items like expected return shape and permission prerequisites, which are lower risk since the schema fully documents inputs.

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 all seven parameters (including the event_id series link and category_id default) are already documented in the schema. The description only restates the timestamp convention, adding little beyond the structured data — baseline 3 applies.

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 and resource ('create an event on the church calendar') plus the optional series-instance behavior, and prefixes with 'WRITE' to disambiguate it from the read-heavy sibling set (breeze_list_events, breeze_get_event). An agent can distinguish this from breeze_add_person/breeze_add_tag 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?

Clearly establishes the create context and adds a real usage constraint: this server cannot delete events, so mistakes must be fixed in the Breeze app. It doesn't route the agent to supporting siblings it would likely need (e.g., breeze_list_calendars for category_id, breeze_get_event to reuse event_id), 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.