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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds meaningful behavioral context ('rows appear only for detected changes to tracked fields', 'recent' implying recency ordering), though it does not mention pagination or the ordering guarantee explicitly.

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 front-loaded sentences with essentially no waste; purpose comes first and the routing sentence follows. The sibling-routing sentence is dense but each clause earns its place.

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?

Output schema exists and annotations cover safety, so return-value explanation is unnecessary and the when-to-use guidance is complete. The only gap is that the description requires 'one Chrome Web Store item ID' but the schema exposes no item-id parameter, leaving how to supply it slightly ambiguous.

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 the schema already documents limit and change_type (including the allowed values). The description adds no param-level detail beyond what the schema provides, so the baseline of 3 applies.

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 ('List recent saved changes for one Chrome Web Store item ID') and immediately clarifies a distinguishing trait: rows appear only for detected changes to tracked fields. An agent can tell it apart from history/metrics/item siblings without opening a 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 routes the agent: history for dated metric observations, metrics for trend summaries, item for the current record. The when-to-use decision against alternatives is fully spelled out with no inference required.

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