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

With no annotations provided, the description carries the full disclosure burden. It does communicate that this is a live external FMCSA query and lists the four result domains, which compensates somewhat for the absent output schema, but it says nothing about latency, rate limits, cost, or what is returned when a DOT/MC number has no record or is invalid.

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 front-loaded sentence with no filler; every listed item is a distinct data domain the caller gets back. It reads slightly like a keyword dump, but nothing is wasted and the scope is stated before any detail.

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?

For a two-parameter read-only lookup with no output schema, enumerating the returned data domains covers most of what an agent needs to decide relevance. The remaining gap is behavioral and comparative: no failure/not-found semantics and no framing against lookup_fmcsa_carrier, which is significant given a sibling with a nearly identical name and purpose.

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 both parameters are already documented with examples in the input schema. The description adds only the high-level framing that both USDOT and MC identifiers feed the query; it does not clarify that dot_number is required and mc_number is an optional alternate or supplementary identifier, which is exactly the nuance an agent would need.

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 names a specific verb ('Query') and resource (FMCSA USDOT/MC carrier) and enumerates the exact data domains returned: operating authority, BIPD insurance, BOC-3 process agent, and 2027 UCR. That is far more specific than a generic lookup, but it never distinguishes this tool from the near-identical sibling lookup_fmcsa_carrier, leaving the agent unable to tell the two apart from the text alone.

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?

There is no explicit when-to-use or when-not-to-use guidance, and no mention of the obvious alternative lookup_fmcsa_carrier. The word 'live' weakly implies real-time verification versus a cached lookup, but the agent must infer which sibling to call and under what circumstances.

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