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

Adds real context beyond the annotations: the change is immediately public ('Guests see it on your website right away'), it 'reaches other people' and requires per-call confirmation, and it needs a Cotlet API key with app access. It doesn't cover reversibility or the fate of fields not passed, but for a non-destructive mutation the disclosure is strong.

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?

The purpose is front-loaded, but the public-visibility point is stated twice ('Guests see it on your website right away' and 'shows on your public website at once, so guests can see it before any email goes out'), and the confirmation behavior is repeated. Tightening would improve it.

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?

Given the 3-param schema at full coverage and the presence of annotations covering the safety profile, the description supplies the extra pieces an agent needs: auth requirements, public side effect, and confirmation etiquette. No output schema exists, but nothing critical for correct invocation 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 description coverage is 100%, so the schema already documents event_id, schedule_item_id, and the fields string with its allowed keys. The description only hints at fields ('the new time or venue'), adding no syntax or format detail beyond the schema. 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 ('Change') and resource ('an event on your Schedule page') and clarifies it is a partial update ('Changes the fields you pass on one Schedule event'). It does not name a sibling alternative to distinguish it from list_schedule or other Joy tools, but the verb+resource is unambiguous.

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?

Gives workflow guidance ('By default you confirm each call; you can switch that off... Reaches other people: confirm with the user before each call'), which implies when care is needed. However, it never states when to use this tool versus alternatives (e.g., joy_list_schedule to find the IDs, or create/delete variants), so selection guidance is only implied.

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