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

Annotations already declare readOnlyHint=true, so the description doesn't need to restate that. It adds value by specifying the order (newest first) and the output fields (change date and affected crawler), which are not in the annotations. However, it doesn't mention potential pagination behavior (though limit is in schema) or how many results are returned by default, so it provides moderate transparency but not exhaustive.

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 three sentences, concise and front-loaded with the core purpose. The key use case is mentioned at the end, which could be moved earlier for better prominence, but there is no fluff or redundancy. It earns its place with useful scoping details.

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?

For a read-only list tool with a well-defined schema (100% coverage on parameters) and no output schema, the description covers the essential behavior: what it lists, the order, the filters, and the use case. It doesn't describe what the response looks like (but no output schema is present), which is a minor gap, but given the simplicity, it's sufficiently complete for an agent to call it 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 100%, so the schema already documents all parameters (limit, since, entity). The description restates that 'since' filters by date and 'entity' filters by crawler, which adds a small layer of context (e.g., which parameter corresponds to which filter), but it doesn't go beyond what the schema provides, so the baseline of 3 is appropriate.

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 clearly states the tool lists recorded changes to claims, with a specific resource (Rattlesnakes By Mail) and a clear scope (newest first, with change date and affected crawler). It distinguishes itself from siblings by emphasizing its filtering capabilities and its role in detecting crawler policy updates, which sets it apart from lookup_crawler and other tools.

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 description gives explicit context on when to use this tool: to detect crawler policy updates published after a given date, which implies it is for monitoring changes rather than looking up current state (which would be lookup_crawler). It mentions filtering by date and crawler, but does not explicitly state when not to use it or name alternative tools directly, so it misses the full 'when-not' guidance.

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