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

With no annotations, the description carries the full behavioral burden and does so well: paid-only-on-returned-rows with zero-row calls free, a hard 100-row cap that overrides the requested limit, Active-only default overridden by include_inactive, and an explicit disclosure that contact fields were removed and why. This is exactly the context annotations would otherwise have to supply.

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?

Information-dense and front-loaded with the payment rule, then tier semantics, then defaults/caps, then the missing-contact-fields caveat. The rhetorical aside about 'the sharpest version of that risk in this product' is editorial padding that costs a point.

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?

No output schema and no annotations, so the description is the sole source of behavior — and it covers pricing, row caps, default filtering, and the removed-fields risk. The gaps are the unexplained filter parameters (state, cargo_type, authority_status) and any description of the returned record shape beyond what is excluded.

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 compensate for six parameters. It explains safety_tier (1–6 scale, derived value, no-tier non-match), include_inactive, and the limit cap, but state, cargo_type, and authority_status are left completely undefined in both schema and description — half the surface remains undocumented.

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+resource ('Filtered carrier search') and immediately frames it as a 'filterable, multi-result endpoint' that returns no contact details, contrasting with lookup_carrier's claimed-identity lookups. An agent can distinguish it from lookup_carrier and find_carrier_by_mc without opening any 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?

Names the alternative (lookup_carrier's claimed_name/claimed_street) and the condition that selects it ('if you need to confirm a specific carrier's claimed identity'), and explains the safety_tier matching rule including the 'never matches' no-tier case. It does not state when to prefer the other sibling search tools (find_carrier_by_mc, get_safety_history), so explicit when-not guidance is incomplete.

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