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

With no annotations provided, the description carries the full behavioral burden. It usefully states the returned fields (airline name, IATA code, tracking site), but it does not mention failure behavior for an unknown prefix, idempotency, or data source. For a simple resolver this is adequate, but it leaves meaningful operational details unstated.

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?

The description is two sentences and front-loads the action, input, and return fields. The analogy is brief and earns its place by clarifying the lookup pattern. There is no redundant or filler content.

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 simple one-parameter lookup with no output schema, the description explains the useful return values (airline name, IATA code, cargo tracking site), which compensates well for the missing output schema. The main gap is the absence of behavior for invalid or unknown prefixes. Otherwise it is complete enough for correct invocation.

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%, and the schema already defines the single 'prefix' parameter as a 3-digit AWB prefix with an example. The description repeats that it is a '3-digit IATA AWB prefix' but adds no format rules, validation notes, or examples beyond the schema. The baseline of 3 applies when the schema already documents parameters fully.

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 uses a precise verb ('Resolve') and resource ('3-digit IATA AWB prefix') and specifies the resulting data: airline name, IATA code, and cargo tracking site. Its function is clearly distinct from the sibling tools air_rate_quote and track_awb, so an agent can identify it without inspecting the 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?

Usage is implied by the description: use it to map an AWB prefix to airline details. However, there is no explicit guidance on when to choose this tool over track_awb or air_rate_quote, nor any exclusions or prerequisites. The analogy to a container-prefix lookup provides context but not routing guidance.

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