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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds real context beyond that: it performs live on-chain lookup across four named networks, returns a private HMAC-SHA256 receipt, and triggers immediate unlock of the bundle with zero human intervention. It does not explain failure/pending behavior or how long verification takes, which keeps it from a 5.

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?

It is a single front-loaded sentence that begins with the action verb and packs the inputs, networks, outputs, and side effect without filler. The density of backticked identifiers makes it slightly heavy to parse, but nothing is redundant.

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?

With four well-documented parameters and no output schema, the description does the important extra work of naming the returned receipt_hmac_sha256 and the downstream capability it unlocks. What is missing is edge-case coverage: verification failure, pending confirmations, and where the deposit_address itself comes from.

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%, with enums and defaults already documented for token and network, so the schema carries the parameter burden. The description reinforces the network set and token set and ties tx_hash to the job's deposit_address, but adds no format or constraint details beyond what the schema states.

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 a precise verb and resource: submit an on-chain USDT/USDC tx_hash for a job's watch-only deposit_address and receive an HMAC-SHA256 receipt. It also names the concrete downstream effect (unlocking calligraphy_download_fab_bundle), which lets an agent distinguish it from sibling payment paths such as calligraphy_create_coinbase_checkout.

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 rather than stated: an agent can infer this is the post-payment verification step after sending funds to the deposit_address, and that it gates the bundle download. However, there is no explicit when-not guidance (e.g. what to do if the payment was made via Coinbase checkout, or what to do when verification fails), so the routing decision against alternative payment/verification siblings is left to inference.

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