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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds value beyond that by disclosing ordering (newest first), the fields returned per entry, and the three actor classes (merchant, Xyla, assistant), which tells the agent how to interpret authorship of each 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?

One sentence, front-loaded with the verb and resource, with the return contents delivered as a tight colon-separated list. No filler and nothing structurally misplaced.

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?

There is no output schema, so the description must describe the return shape itself, and it does: ordering, per-entry fields, actor attribution, and the undo id. For a one-parameter read-only list tool, an agent has everything needed to call and interpret it.

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% and the single `limit` parameter already documents the default of 10 and a max of 50. The description adds nothing about paging or limit behavior, so it sits at the baseline for a fully documented schema.

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 and resource ("Lists recent changes to the shop's Xyla settings") and enumerates exactly what each entry contains: what changed, before/after, actor, and undo id. It is clearly distinguishable from get_settings (current state) and change_settings (mutation), and explicitly links to undo_change.

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 phrase "the undo id to pass to undo_change" gives an explicit routing cue to the sibling that consumes this output, and "newest first" sets an expectation about the review workflow. It lacks an explicit when-not clause (e.g., use get_settings for current values rather than history), so it falls short of a 5.

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