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

Annotations only declare readOnly=false, destructive=false, openWorld=true; the description goes well beyond that by disclosing that date/time edits trigger emails to guests, producers and audience, auto-update the Google Calendar invite, and require per-call confirmation (which can be toggled off) plus a Cotlet API key. These are meaningful side effects and prerequisites an agent could not learn from the structured fields.

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 in the first sentence, followed by behavioral details and guardrails in a logical order. It is slightly long with some operational meta-instructions, but every sentence carries non-redundant information.

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 mutation tool with no output schema, the description covers side effects, confirmation policy, auth requirements and partial-update semantics. Only gap is the unmentioned 'who is invited' capability lacking a parameter, leaving a small inconsistency an agent might trip over.

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 would be 3. The description adds genuine semantic value by stating the partial-update contract (only passed fields change, the rest are left intact) and by tying start/end changes to the notification behavior, which the schema alone does not convey.

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 opens with a concrete verb-plus-resource statement and enumerates the mutable properties (rename, reschedule, invitees), which clearly distinguishes it from siblings like riverside_schedule_session and riverside_cancel_session. Minor deduction because 'change who is invited' has no corresponding parameter in the schema, so part of the stated purpose is not actionable with this tool.

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?

It clarifies the update semantics ('changes the fields you pass and leaves the rest'), which implies when to use this versus a full re-create. However, it never explicitly names riverside_schedule_session or riverside_invite_guest as alternatives, so the agent must infer tool routing.

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