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

The description goes far beyond the annotations, detailing that the tool reads live nonce/gas/fees, never sponsors gas, never holds keys, and never enforces allowlists or spend limits. It also explains the fallback behavior for token_decimals and the privacy encryption feature. Annotations already indicated readOnly, idempotent, and non-destructive, and the description aligns perfectly while adding significant operational context.

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 description is well-structured with clear sections (supported chains, token, gas, raw calldata, privacy) and front-loaded with the core purpose. While it is fairly long, each sentence adds necessary detail for a complex tool with 8 parameters. It could be slightly tighter, but overall it is efficient and well-organized.

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?

Given the tool's complexity (8 parameters, multiple chain-specific behaviors, raw calldata, privacy, token types) and the presence of an output schema, the description covers all relevant aspects. It explains edge cases, limitations, and additional context not in the schema. No gaps are apparent.

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%, and the description adds substantial meaning to every parameter. For example, it explains the token field can be a symbol or contract address, with chain-specific options. It clarifies that amount is in human units, that data is for raw EVM calls, and that private only works on skale-base-sepolia. This exceeds basic parameter documentation.

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 clearly states the tool's purpose: 'Build an unsigned native or token transfer transaction for a supported chain, from an explicit sender you provide.' It explicitly distinguishes itself from signing or broadcasting, making the action unambiguous. There are no sibling tools that perform a similar function, so no confusion.

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 provides clear context on when to use the tool: it is free, read-only, never signs or broadcasts, and requires an explicit sender. It also explains that gas is paid by the sender later. While there are no direct alternative tools to compare, the description gives sufficient guidance on the tool's limitations and prerequisites.

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