history

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It reveals a non-obvious behavior: revisions follow the item across changes and moves, so the history stays accurate over time. This is genuinely useful context beyond what the schema or tool name communicates.

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 two sentences with no filler. The core purpose is front-loaded, and the second sentence earns its place by explaining how to obtain the parameter and why the tool is valuable for a common question.

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 single-parameter tool with an output schema, the description provides enough to invoke it correctly: what it returns, where the parameter comes from, and its key tracking behavior. It could be more explicit about ordering, pagination, or read-only guarantees, but those are not critical given the output schema and low 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 schema provides only a name and type for item_key with 0% description coverage. The description adds useful provenance—'item_key comes from any other tool's output'—which tells an agent where to source the value. However, it does not clarify the format, constraints, or what qualifies as a valid item_key, so it only partially compensates for the schema gap.

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 identifies the resource as the revision history of a single item ('Every revision of one item'), which is distinct from sibling tools like read_document or search. It lacks an explicit action verb like 'retrieves' or 'lists', and its phrasing is more definitional than operational, so it stops short of a 5.

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 concrete guidance: item_key should be obtained from any other tool's output, and this is positioned as the reliable way to answer 'has this been updated since I read it'. It does not explicitly name alternative tools or list exclusion criteria, but the use case and prerequisite are clear.

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