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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the bar is lower. The description adds a genuinely useful trait beyond them: reg: content is "read live from the eCFR," telling the agent results are freshly fetched rather than cached. It does not mention failure behavior for invalid ids or any rate limiting.

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?

A single dense sentence with the verb front-loaded and no filler. Every clause (return value, provenance, id formats, live-read note) carries information.

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 states the return value (full text) and where valid ids originate, which is what a one-parameter read tool needs. Minor gaps remain around invalid-id handling and the overlap with read_regulation, but nothing essential to invocation 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 coverage is 100% and the schema only says "A document id from search," but the description supplies the actual id grammar: overview:<topic>, records:<requirement>, form7220, law2025, tennessee, reg:<section>[(paragraph)], plus a concrete example (reg:1.45-8(d)). This is meaningfully more than the schema provides and is enough to construct a valid id.

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 and resource ("Returns the full text of a document") and ties it to the discovery step ("found with search"), so an agent knows this is the retrieval counterpart to search. It stops short of differentiating from the sibling read_regulation, which also deals with regulation content and could be confused with the reg:<section> ids this tool accepts.

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 "found with search" implies the intended workflow (search first, then fetch by id), but there is no explicit when-to-use statement, no when-not-to-use, and no named alternative such as read_regulation. Usage is inferable rather than stated.

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