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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds the row shape (step, status, entry time, next due, goal reached), which is useful but is closer to output content than behavioral context; it says nothing about paging behavior or authorization.

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?

A single sentence with zero padding that front-loads the scoping fact ('one run each') before the returned fields. Appropriately sized for a list tool; slight loss for the informal phrasing over a crisp statement of 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?

With no output schema, the description usefully enumerates the returned fields, which fills part of the gap. However, the undocumented filter enum and the absence of any boundary with sibling run/people tools leave meaningful gaps for an agent calling this 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 description coverage is 80%, so the schema already documents limit, offset, and search, and the description adds no parameter detail. The filter enum (all/in/goal/finished/left) has no description in either place, so its semantics remain undefined.

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 gives a specific verb+resource (list people who entered a journey, one run each) and enumerates the fields returned, so an agent knows exactly what this returns. It does not, however, differentiate from the close sibling list_journey_people or get_journey_run, leaving the agent to infer the difference.

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?

Usage is implied by 'everyone who entered a journey,' but there is no explicit when-to-use statement, no exclusion, and no pointer to alternatives such as list_journey_people or get_journey_run. An agent must infer the retrieval scenario on its own.

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