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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint), lowering the bar. The description adds genuine value by disclosing what comes back: the section's plain text, its current-as-of date, and the official eCFR URL. It does not mention rate limits or the point-in-time behavior of the date parameter.

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?

Three tight sentences: purpose first, then a concrete example, then return contents. Every sentence earns its place and nothing is redundant.

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 no output schema, the description correctly compensates by naming the return fields (plain text, currency date, eCFR URL). Combined with full schema coverage and safety annotations, an agent has what it needs to invoke it correctly; only the optional date parameter's semantics go unaddressed in prose.

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 all four parameters are already documented in the schema. The description reinforces title/part/section with a concrete example but adds no new syntax or constraints, and does not mention the optional 'date' parameter at all. Baseline 3 is appropriate when the schema does the heavy lifting.

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?

Specific verb ('Get') plus precise resource ('current text of a specific Code of Federal Regulations section'), and the example citation (title 40, part '98', section '98.411') makes the identifier-based retrieval unambiguous. It does not explicitly name or contrast with siblings like reg_cfr_search or reg_cfr_titles, so differentiation is only implied.

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 phrase 'specific ... section' combined with a worked example implies the use case (you already know the exact citation), but there is no explicit when-to-use statement, no when-not, and no routing to reg_cfr_search for keyword lookup. Usage is inferred rather than stated.

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