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

With no annotations supplied, the description carries the full burden and does so well: it discloses the key-ownership model (you hold the private key, our signer is policy-locked to fee destinations), the auth prerequisite ('copy' scope), and the security guarantee that an API key alone can never bind an owner key. This is meaningful behavior beyond the schema, not a restatement of it.

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 critical facts (what it creates, what you send, the two-call flow, the scope requirement) are front-loaded in a logical order. A few clauses lean promotional ('keeps your Hyperliquid trading agent from expiring on you') and could be trimmed without losing decision-relevant information.

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 3-parameter creation tool with no output schema and no annotations, the description covers the write's security model, its auth requirement, the multi-step handshake, and what the first call returns (a message naming the key fingerprint). Nothing an agent needs in order to invoke it correctly is missing.

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 the sequencing semantics the schema only gestures at: owner_public_key alone on call one, then owner_public_key + nonce + signature on call two, with the signature specified as EIP-191 over the returned message. This clarifies the stateful relationship between the three parameters.

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 opens with a specific verb+resource+scope: 'Create the copy wallet needed for LIVE copying.' This distinguishes it from siblings like get_copy_wallet, create_trading_wallet, and follow_leader without the agent needing to open any 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?

It states the precondition ('Requires the copy scope') and gives an explicit two-call procedure, including that the first call takes only owner_public_key and the second adds nonce + signature. It stops short of naming an alternative for agents that already hold a wallet (e.g., get_copy_wallet), so the routing guidance is implicit rather than explicit.

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