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

Annotations only declare destructiveHint=true, but the description discloses the key destructive mechanism: this never sends a breaks array, and omitted breaks are removed by the API, so the agent should re-check breaks afterward. That is exactly the non-obvious mutation consequence an agent needs, and it is consistent with the destructive hint.

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?

Three sentences, front-loaded action first, then prerequisites and the destructive caveat, then the endpoint reference. No filler; each sentence carries distinct, actionable 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 12-param destructive mutation with no output schema, the description covers the prerequisite (fetch first), the destructive side effect (breaks removal), the required fields, and the underlying endpoint. An agent has everything needed 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 schema already documents all 12 parameters and even notes the required-even-if-unchanged semantics. The description adds workflow meaning by tying the required trio (start_time, end_time, location_id) to the fetch-first pattern the agent must follow.

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 (a shift) and enumerates the concrete operations — reassign, move, change position or notes. An agent can distinguish this from get_shift, create_shift, and publish_shifts without opening any 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?

Explicitly instructs the agent to fetch the shift first (get_shift) and pass back the required fields, which is real when-and-how guidance. It stops short of naming sibling alternatives like create_shift or publish_shifts for competing outcomes, so it is clear context rather than full routing.

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