Data changelog

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

Annotations already cover the safety profile (readOnly, idempotent, non-open-world), but the description adds real behavioral context: the crawler caps the log at 20 refreshes, so the tool covers the full retained history rather than a truncated slice. That retention/cap behavior is exactly the kind of trait annotations cannot express, though it says nothing about ordering or response shape.

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 that lead with the core purpose before qualifying scope and the mirroring resource URI. The long parenthetical is information-dense rather than wasteful, though it slightly buries the retention fact.

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?

With an output schema present, return-value explanation is unnecessary, and the description covers purpose, retention window, scope caveat, and alternate access path. The one gap is that the only input parameter is undocumented in both the schema and the description.

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 single `limit` parameter has 0% schema description coverage and is never named in the description, so its role (number of entries returned) and default of 5 are left implicit. The description does partially compensate by explaining the 20-entry cap, which gives the schema's maximum=20 meaning, but it never connects that to the `limit` argument itself.

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+resource: what changed between data versions of the server's crawled artifact, scoped to crawl-to-crawl differences in finops.org content. It explicitly disambiguates from a Foundation-published changelog, so the agent knows exactly what this returns and that no sibling tool covers this ground.

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?

Gives clear context for when this applies (checking crawl-to-crawl diffs in the retained history) and rules out a common misreading ('not a Foundation-published changelog'), plus points to the equivalent resource at finops://framework/meta/changelog. It stops short of an explicit when-to-use/when-not rule against sibling tools, but no sibling offers changelog data.

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