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

Annotations only convey generic flags (readOnly false, idempotent false, etc.), so the description carries the behavioral burden. It discloses the creation side effect, the date/time generation rules, the returned fields (slug, public url, adminUrl, adminKey), and the important security instruction to keep adminKey private. This goes well beyond the structured annotation data and has no contradiction.

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 description is dense but efficient: purpose first, then the generation rule, then return values, then an illustrative example. The 'days' aside is slightly ambiguous and adds some confusion, but every major sentence earns its place and the structure is front-loaded.

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?

Since there is no output schema, describing returns (slug, public url, adminUrl, adminKey) is essential and is done clearly. It also covers the core input semantics and example scale. It would be more complete with an explicit clarification of the optional `days` parameter and the endDate-vs-days precedence, but overall it equips an agent to call it correctly.

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, but the description adds a conceptual algorithm and a concrete example mapping natural language to parameters (title, startDate, endDate, hourFrom, hourTo, durationMinutes, startStepMinutes). The weakness is that the 'or give days instead' option is left vague and does not clarify the confusing `days` property in the schema, so it does not fully resolve every parameter.

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+resource: creates a sync.day availability poll and returns the share link. The description also explains how candidate days/times are generated, which makes the purpose concrete. It does not explicitly distinguish itself from siblings like decide_time or update_event, so it stops short of a 5.

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?

No explicit guidance on when to use create_event versus alternatives. The only related-tool hint is that adminKey is needed later for update_event / remove_participant, which is forward-looking usage advice, not tool-selection guidance. An agent must infer when to use this tool from the name/title.

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