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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds that the result includes 'who changed what and when' but does not disclose pagination behavior, ordering, or that the default limit is 20 (though the schema covers the limit parameter). This is useful context but not rich behavioral disclosure beyond annotations.

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?

The description is a single, front-loaded sentence with no filler. Every word adds value: 'Get', 'change history', 'saved item', and 'who changed what and when'.

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?

The tool is a simple read-only history lookup. The schema covers both parameters, annotations cover safety and idempotency, and the description precisely explains the nature of the returned data. No output schema is needed because the return type is clear from the description. It is complete for its complexity.

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?

The input schema has 100% coverage, with both item_id and limit fully described. The description does not add additional parameter-level meaning 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?

The description uses a specific verb ('Get') and a specific resource ('change history for a saved item'), and further clarifies the payload ('who changed what and when'). This clearly distinguishes it from sibling tools like get_item (current state) and get_collection_activity (collection-level activity).

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?

It clearly implies the tool is for retrieving change history of an individual item, which gives context for when to use it. However, it does not explicitly mention alternatives or situations where a different tool (e.g., get_item for current state) would be preferable, so it lacks explicit exclusions.

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