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

No annotations are provided, so the description carries full burden. It notes pricing ($0.25/call) and states 'in one call', implying a single request. However, it does not disclose read-only nature, rate limits, or potential response size. The behavioral details are adequate but not exhaustive.

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?

Description is a single dense but informative sentence listing all data components. It is not overly verbose and covers key points efficiently. Minor improvement could be structuring as a bullet list, but current form is acceptable.

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?

Given no output schema, the description thoroughly enumerates return data sections (census, authority history, insurance, safety rating, SaferGrade breakdown, inspection/crash summaries, timeline). It omits some interpretation details but is sufficient for domain users. Sibling tools provide context for alternatives.

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?

Only one parameter (usdot) with schema description providing example and type. Description does not add significant meaning beyond the schema. Since schema coverage is 100% and parameter is straightforward, baseline score of 3 is appropriate.

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?

Description clearly states it returns a comprehensive FMCSA dossier for a carrier by USDOT number, listing specific data components (census identity, authority records, insurance, safety rating, SaferGrade, inspections, crashes). This distinguishes it from sibling tools like fmcsa_carrier_lookup or fmcsa_carrier_score which focus on individual aspects.

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?

Description implies this is the one-call complete file, suggesting use when a full picture is needed. While it does not explicitly list alternatives or exclusions, the sibling tools' names and this description provide enough context for selection.

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