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

No annotations are provided, so the description carries the full behavioral burden. It discloses that the slot is validated against the fleet's real range and that the result is canonical, with the Card as source of truth. It does not mention error handling or side effects, but the read-only resolver behavior is reasonably transparent.

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 arrow expression front-loads the core contract in one compact line, and the second sentence adds just enough behavioral context. There is no fluff or repetition of schema details.

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 two-parameter resolver with no output schema, the description specifies the output, the validation behavior, and the trust model. It could be more complete by naming sibling alternatives and describing what happens on validation failure, but the core calling context is present.

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%, so the baseline is 3. The description adds meaning by explaining that the slot is validated against the fleet's real range, which goes beyond the schema's regex pattern, and by clarifying the relationship between fleet, slot, and the resulting URL.

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 states the exact function: it maps a fleet and slot to the canonical Card URL. The word 'canonical' and the line about the Card being the source of truth distinguish this resolver from sibling tools like find_carriers and get_carrier_doctrine.

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 description gives clear operational context—after resolving, fetch the Card to confirm the Carrier—but does not explicitly state when to choose this tool over alternatives or when not to use it. Usage is implied rather than spelled out.

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