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

Annotations already declare readOnlyHint=false, destructiveHint=true and idempotentHint=true; the description's valuable addition is the partial-update guarantee that unpassed fields are preserved, which is consistent with idempotentHint. However, for a tool flagged destructive, it says nothing about the consequences of the change, whether it can be undone, or permission requirements, so meaningful behavioral disclosure is missing.

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?

Two sentences, front-loaded with the verb and resource, then the field list, then the partial-update rule. The enumeration is dense but each clause maps to a distinct parameter, so there is essentially no filler; only the long list slightly taxes readability.

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 an 11-parameter mutation tool with 64% schema coverage and no output schema, the description covers most mutable fields and the partial-update semantics, but omits notes and title_en and says nothing about what the destructive flag means in practice. It is adequate to call the tool correctly but not complete given the mutation risk.

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?

With schema coverage at 64% and 11 parameters, the description maps natural-language concepts onto parameters that the schema names tersely: time to starts_at, duration to duration_minutes, place to location, who is responsible to owner, linked vendor or moment to vendor_id/moment_id, guests see it to for_guests. It leaves notes and title_en unaddressed beyond the generic 'title', so it is not fully compensating, but it adds real meaning.

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 concrete verb ('Changes') and resource ('an item of the run of show') and enumerates the mutable facets, so the agent knows this is a partial-update tool distinct from add-/delete-schedule-item. It stops short of naming those siblings explicitly, which keeps it from 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?

The clause 'Only the fields you pass change' is genuine usage guidance: it tells the agent it may send a minimal payload instead of a full object. There is no explicit statement of when to prefer this over add-schedule-item or delete-schedule-item, and no prerequisites such as needing the id from get-schedule (that lives only in the schema).

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