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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, providing a clear safety and idempotency profile. The description adds context about the source (eCFR/GovInfo) and pricing ($0.01 per call), but does not disclose additional behavioral traits such as default date behavior or what happens for invalid citations. With strong annotation coverage, this is adequate but not enriched.

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 one compact sentence followed by a source note, pricing, and endpoint. Each piece is informative and no unnecessary words are present. The key action and resource are front-loaded.

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 simple read-only tool with full schema coverage, the description is mostly adequate. However, it does not clarify common usage details like whether a title alone is enough to fetch an entire title, how part/section are scoped, or the meaning of 'current' relative to the optional date parameter. These gaps are not severe given the schema's per-parameter examples, but an agent might benefit from a brief usage example.

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 fully documents all four parameters. The description adds only the phrase 'for a citation' and does not explain how to construct a citation or how parameters interact. Baseline 3 is appropriate because the schema carries the parameter documentation burden.

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 fetches current Code of Federal Regulations text for a citation, naming the resource (CFR legal text) and the action (fetch). It is distinguishable from siblings, though it does not explicitly contrast with any sibling that might also deal with legal or reference data.

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 implies usage by specifying 'for a citation' and mentions the source (eCFR/GovInfo), but it does not provide explicit when-to-use guidance or alternatives. Since the sibling list contains many unrelated tools, the lack of an explicit exclusion is not critical, but no direct usage scenario guidance is given.

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