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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds that the journey must be "owned" (a permission/scope constraint) and repeats the at-least-one-field validation rule, but says nothing about failure modes or reversibility of a schedule change.

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 short sentences with zero waste; the capability is front-loaded and the validation constraint follows immediately. Nothing extraneous.

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?

With a full output schema, 100% parameter coverage, and annotations covering the safety profile, the description supplies everything an agent needs to call this correctly: ownership requirement, the two updatable fields, and the minimum-field rule.

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 description coverage is 100%, so name, frequency, and journeyId are already documented in the schema, including the enum values. The description's mapping of "rename" to name and "schedule" to frequency adds only light semantic reinforcement, not new information.

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 specific verbs (rename, change schedule) and the resource (a journey), so an agent knows exactly what mutation this performs. It implicitly distinguishes itself from create_journey, get_journey, and pause/resume_journey, though it doesn't name any sibling explicitly.

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?

"At least one field is required" gives a useful invocation constraint, implying usage over a dedicated tool when both name and schedule change at once. However, it never says when to prefer pause_journey/resume_journey for schedule control or what prerequisites exist, leaving alternatives to inference.

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