Cancel Transfer

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

Goes well beyond the destructive/openWorld annotations by disclosing the internal sequence (mark cancelled locally, withdraw at registry, verify, refund), the restore-on-failure semantics, the TRANSFER_STATE_UNCONFIRMED outcome, and escalation policy. This is exactly the kind of behavior an agent cannot infer from annotations.

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?

Front-loads the what and the confirm-first rule in bold, then walks through the ordering and failure path. Mostly every sentence earns its place, though 'The order is deliberate' is slightly chatty filler around otherwise load-bearing 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 destructive, non-idempotent mutation with no output schema, it supplies the safety preface, the failure/rollback behavior, the error code to expect, and the response fields (withdrawnAtRegistry, registryResultCode, refunded, refundAmount). An agent has everything needed to call and interpret it.

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 both parameters are self-documented, so the baseline is 3. The description never mentions 'domain' or 'dry_run' and adds no syntax or selection meaning 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 (cancels) plus a precise resource and effect (paid inbound transfer, refunds the order). An agent can distinguish this from list_transfers, get_transfer_status, and start_transfer without opening 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?

Gives clear operative context: 'Confirm with the user first' and, on the unconfirmed path, 'escalate to support rather than retrying.' It does not name alternative siblings such as get_transfer_status for inspection, so it stops short of full when/when-not routing.

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