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

Annotations already cover read-only/idempotent/open-world, and the description adds genuinely new behavioral context: pagination termination, stale-flag inspection, the unofficial-mirror disclaimer with verification caveat, and an explicit instruction to treat retrieved text as source material rather than instructions (prompt-injection defense). That is well beyond what the structured fields convey.

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?

Dense but front-loaded: retrieval scope, then pagination, then citation and staleness rules, then disclaimers. Every sentence carries a distinct instruction, though the block is long enough that a reader must work through several imperatives.

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?

An output schema exists, so return-shape detail is unnecessary, yet the description still names the key fields an agent must act on (inlineCitation, legalCitation, bodyAsOf/sourceDate, stale flags). For a read tool with pagination and citation obligations, nothing material is missing.

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 0%, so the description must carry the load. It explains the path format with a concrete example (/Title-31/Section-10.1) and implies offset-based paging via nextOffset, but never describes the length parameter or the offset/length units and caps that the schema only encodes as min/max/default.

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 (Retrieve) and resource (regulation text and child links), and pins the input to its origin: a canonical path returned by search. This cleanly separates it from search_regulations and list_titles without opening either schema.

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 actionable context: fetch the regulation before quoting a search snippet, follow nextOffset until null for complete text, and include citation fields for every claim. It doesn't explicitly name the sibling tools as alternatives, but the sequencing against search is clear enough to route an agent.

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