lookup_citation

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

No annotations are provided, so the description carries the full burden. It meaningfully discloses a non-obvious behavior: large parts return an outline instead of full text, and it gives a follow-up strategy. It could add more about truncation or formatting, but the output schema covers return structure.

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 compact sentences, each carrying necessary information: the core purpose and the important part-vs-section behavioral caveat. No filler or redundant restatement.

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?

The description covers the main retrieval behavior and the key edge case of large parts. The main gaps are the lack of sibling routing and the unexplained max_chars parameter, but the schema provides good examples and the output schema exists.

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 description adds no parameter-level meaning beyond the schema. The citation and date parameters are already well described in the schema, but max_chars has no description there and the tool description does not clarify it either. At 67% schema coverage, the description should have compensated for this 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 states a clear action and resource: 'Retrieve the text of a specific CFR citation.' The added note about large parts returning outlines helps clarify scope, though it does not explicitly distinguish this tool from siblings like search_regulations or browse_structure.

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 when to use the tool: for a specific section citation, and as a follow-up after a part-level outline. However, it does not explicitly mention alternatives or state when not to use this tool versus the sibling tools.

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