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

With no annotations, the description carries the full burden and does meaningful work: it discloses that Pathao/RedX/Paperfly cancellation is executed live upstream while Steadfast is only a request plus portal action links. It stops short of stating irreversibility, idempotency, or what happens when eligibility validation fails.

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?

Three tight sentences, front-loaded with the action and scope, then the automated-carrier case, then the Steadfast exception. No redundant restatement of the name or schema.

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 mutation tool with no annotations and no output schema, the carrier-behavior split is covered, but the description leaves the agent without outcome information: no indication of irreversibility, no failure/eligibility-failure semantics for the automated carriers, and no sense of what the tool returns.

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, but the description adds real meaning beyond the enum: it maps specific courier values to distinct backend behaviors. The reason and consignment_id parameters gain no extra semantics beyond the schema.

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 (cancel) and resource (existing parcel consignment), and names the four carriers it operates on. It also distinguishes the two cancellation modes, so an agent knows exactly what operation it is invoking versus siblings like create_parcel or track_parcel.

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 word 'existing' implies the consignment must already exist, and the Steadfast branch mentions eligibility validation, but there is no explicit when-not-to-use guidance (e.g. already delivered, already cancelled) or direction to an alternative flow such as resolve_ndr_issue for in-flight delivery problems.

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