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

Beyond annotations, the description explains that omitted fields keep their current values, that already-scheduled Pins retain their assigned time, and that moving a slot only affects where future Pins land. This is important mutation context, especially for a tool annotated as destructive and idempotent, and it does not contradict those annotations.

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 front-loaded with the primary use case, then layers in the rebuild alternative, mutation side effects, and account-selection guardrail. Every sentence contributes operational guidance, and no information is repeated without purpose.

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?

The description covers the mutation's effects, required inputs, omitted-field behavior, alternative tool selection, and account-selection prerequisites. Since an output schema exists, it does not need to explain return values, and it provides enough context for an agent to invoke the tool 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 schema already documents parameter formats and sources. The description adds useful semantics beyond the schema by stating that omitted fields are preserved and that at least one of dayPreference, time, or timezone is required, though it does not repeat every parameter detail.

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 states a specific verb and resource: moving/changing an existing smart schedule timeslot's day, time, or timezone. It also explicitly distinguishes this from rebuilding a schedule, naming the alternative behavior that would discard the whole schedule and generate a new one. An agent can identify the tool's scope without opening the 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?

It gives explicit usage conditions, including that timeslotId comes from list_timeslots, that only changed fields should be passed, and that at least one of dayPreference, time, or timezone is required. It also contrasts this with rebuild_schedule and gives account-selection guidance when multiple Pinterest accounts exist.

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